From cdc1cd6850db5ed537b03493d3b915abd689e51c Mon Sep 17 00:00:00 2001
From: Tim Cadman <41470917+timcadman@users.noreply.github.com>
Date: Fri, 30 Oct 2026 10:54:17 +0100
Subject: [PATCH 1/2] Rename client helpers to camelCase and use newobj helper

---
 R/ds.Boole.R                                  | 10 ++---
 R/ds.abs.R                                    |  6 +--
 R/ds.asCharacter.R                            |  6 +--
 R/ds.asDataMatrix.R                           |  6 +--
 R/ds.asFactor.R                               |  2 +-
 R/ds.asFactorSimple.R                         |  2 +-
 R/ds.asInteger.R                              |  6 +--
 R/ds.asList.R                                 |  6 +--
 R/ds.asLogical.R                              |  6 +--
 R/ds.asMatrix.R                               |  6 +--
 R/ds.asNumeric.R                              |  6 +--
 R/ds.assign.R                                 |  6 +--
 R/ds.auc.R                                    |  2 +-
 R/ds.boxPlot.R                                |  4 +-
 R/ds.boxPlotGG.R                              |  2 +-
 R/ds.boxPlotGG_data_Treatment.R               |  2 +-
 R/ds.boxPlotGG_data_Treatment_numeric.R       |  2 +-
 R/ds.boxPlotGG_numeric.R                      |  2 +-
 R/ds.boxPlotGG_table.R                        |  2 +-
 R/ds.bp_standards.R                           |  6 +--
 R/ds.c.R                                      |  6 +--
 R/ds.cbind.R                                  |  6 +--
 R/ds.changeRefGroup.R                         |  6 +--
 R/ds.class.R                                  |  2 +-
 R/ds.colnames.R                               |  4 +-
 R/ds.completeCases.R                          |  6 +--
 R/ds.contourPlot.R                            | 18 ++++----
 R/ds.cor.R                                    |  2 +-
 R/ds.corTest.R                                |  2 +-
 R/ds.cov.R                                    |  2 +-
 R/ds.dataFrame.R                              | 10 ++---
 R/ds.dataFrameSort.R                          |  4 +-
 R/ds.dataFrameSubset.R                        |  6 +--
 R/ds.densityGrid.R                            | 10 ++---
 R/ds.dim.R                                    |  2 +-
 R/ds.dmtC2S.R                                 |  6 +--
 R/ds.elspline.R                               |  6 +--
 R/ds.exists.R                                 |  2 +-
 R/ds.exp.R                                    |  6 +--
 R/ds.gamlss.R                                 |  6 +--
 R/ds.getWGSR.R                                |  6 +--
 R/ds.glm.R                                    |  2 +-
 R/ds.glmPredict.R                             |  6 +--
 R/ds.glmSLMA.R                                |  6 +--
 R/ds.glmSummary.R                             |  6 +--
 R/ds.glmerSLMA.R                              |  6 +--
 R/ds.heatmapPlot.R                            | 18 ++++----
 R/ds.hetcor.R                                 |  2 +-
 R/ds.histogram.R                              |  4 +-
 R/ds.igb_standards.R                          |  6 +--
 R/ds.isNA.R                                   |  2 +-
 R/ds.isValid.R                                |  2 +-
 R/ds.kurtosis.R                               |  2 +-
 R/ds.length.R                                 |  2 +-
 R/ds.levels.R                                 |  2 +-
 R/ds.lexis.R                                  |  2 +-
 R/ds.list.R                                   |  6 +--
 R/ds.listDisclosureSettings.R                 |  2 +-
 R/ds.lmerSLMA.R                               |  6 +--
 R/ds.log.R                                    |  6 +--
 R/ds.ls.R                                     |  2 +-
 R/ds.lspline.R                                |  6 +--
 R/ds.make.R                                   |  6 +--
 R/ds.matrix.R                                 |  6 +--
 R/ds.matrixDet.R                              |  6 +--
 R/ds.matrixDet.report.R                       |  2 +-
 R/ds.matrixDiag.R                             |  7 +--
 R/ds.matrixDimnames.R                         |  6 +--
 R/ds.matrixInvert.R                           |  6 +--
 R/ds.matrixMult.R                             |  6 +--
 R/ds.matrixTranspose.R                        |  6 +--
 R/ds.mdPattern.R                              |  2 +-
 R/ds.mean.R                                   |  2 +-
 R/ds.meanSdGp.R                               |  6 +--
 R/ds.merge.R                                  |  6 +--
 R/ds.metadata.R                               |  2 +-
 R/ds.mice.R                                   |  2 +-
 R/ds.names.R                                  |  2 +-
 R/ds.ns.R                                     |  6 +--
 R/ds.numNA.R                                  |  2 +-
 R/ds.qlspline.R                               |  6 +--
 R/ds.quantileMean.R                           |  2 +-
 R/ds.rBinom.R                                 | 10 ++---
 R/ds.rNorm.R                                  |  8 ++--
 R/ds.rPois.R                                  |  4 +-
 R/ds.rUnif.R                                  |  8 ++--
 R/ds.rbind.R                                  |  6 +--
 R/ds.reShape.R                                |  2 +-
 R/ds.recodeValues.R                           |  6 +--
 R/ds.rep.R                                    |  7 +--
 R/ds.replaceNA.R                              |  6 +--
 R/ds.rm.R                                     |  2 +-
 R/ds.rowColCalc.R                             |  6 +--
 R/ds.sample.R                                 |  7 +--
 R/ds.scatterPlot.R                            |  6 +--
 R/ds.seq.R                                    |  2 +-
 R/ds.setSeed.R                                |  2 +-
 R/ds.skewness.R                               |  2 +-
 R/ds.sqrt.R                                   |  6 +--
 R/ds.summary.R                                |  2 +-
 R/ds.table.R                                  |  7 +--
 R/ds.tapply.R                                 |  2 +-
 R/ds.tapply.assign.R                          |  6 +--
 R/ds.unList.R                                 |  6 +--
 R/ds.unique.R                                 |  6 +--
 R/ds.var.R                                    |  2 +-
 R/utils.R                                     | 44 +++++++++----------
 tests/testthat/test-arg-per-study-arguments.R | 18 ++++----
 tests/testthat/test-utils.R                   | 14 ++++++
 109 files changed, 244 insertions(+), 346 deletions(-)
 create mode 100644 tests/testthat/test-utils.R

diff --git a/R/ds.Boole.R b/R/ds.Boole.R
index 881ebbb74..ae4e81b10 100644
--- a/R/ds.Boole.R
+++ b/R/ds.Boole.R
@@ -104,7 +104,7 @@
 #'
 ds.Boole<-function(V1=NULL, V2=NULL, Boolean.operator=NULL, numeric.output=TRUE, na.assign="NA",newobj=NULL, datasources=NULL){
 
-  datasources <- .set_datasources(datasources)
+  datasources <- .resolveDatasources(datasources)
 
   # check if user has provided the name of the column or scalar that holds V1
   if(is.null(V1)){
@@ -127,9 +127,7 @@ ds.Boole<-function(V1=NULL, V2=NULL, Boolean.operator=NULL, numeric.output=TRUE,
   }
 
   # create a name by default if user did not provide a name for the new variable
-  if(is.null(newobj)){
-    newobj <- "boole.newobj"
-  }
+  newobj <- .resolveNewobjName(newobj, "boole.newobj")
 
   #convert Boolean operator to numeric
 
@@ -163,9 +161,7 @@ ds.Boole<-function(V1=NULL, V2=NULL, Boolean.operator=NULL, numeric.output=TRUE,
   }
 
   # if no value spcified for output object, then specify a default
-  if(is.null(newobj)){
-    newobj <- paste0(V1,"_Boole")
-  }
+  newobj <- .resolveNewobjName(newobj, paste0(V1,"_Boole"))
 
   # CALL THE MAIN SERVER SIDE FUNCTION
   calltext <- call("BooleDS", V1, V2, BO.n, na.assign, numeric.output)
diff --git a/R/ds.abs.R b/R/ds.abs.R
index 625591a84..b434e30c1 100644
--- a/R/ds.abs.R
+++ b/R/ds.abs.R
@@ -73,15 +73,13 @@
 #'
 ds.abs <- function(x=NULL, newobj=NULL, datasources=NULL){
 
-  datasources <- .set_datasources(datasources)
+  datasources <- .resolveDatasources(datasources)
 
   if(is.null(x)){
     stop("Please provide the name of the input object!", call.=FALSE)
   }
 
-  if(is.null(newobj)){
-    newobj <- "abs.newobj"
-  }
+  newobj <- .resolveNewobjName(newobj, "abs.newobj")
 
   cally <- call("absDS", x)
   DSI::datashield.assign(datasources, newobj, cally)
diff --git a/R/ds.asCharacter.R b/R/ds.asCharacter.R
index 700b90b12..f2b359ecf 100644
--- a/R/ds.asCharacter.R
+++ b/R/ds.asCharacter.R
@@ -56,15 +56,13 @@
 #' 
 ds.asCharacter <- function(x.name=NULL, newobj=NULL, datasources=NULL){
 
-  datasources <- .set_datasources(datasources)
+  datasources <- .resolveDatasources(datasources)
 
   if(is.null(x.name)){
     stop("Please provide the name of the input vector!", call.=FALSE)
   }
   
-  if(is.null(newobj)){
-    newobj <- "ascharacter.newobj"
-  }
+  newobj <- .resolveNewobjName(newobj, "ascharacter.newobj")
 
 	calltext <- call("asCharacterDS", x.name)
 	DSI::datashield.assign(datasources, newobj, calltext)
diff --git a/R/ds.asDataMatrix.R b/R/ds.asDataMatrix.R
index 9126b9fc0..140d55bc2 100644
--- a/R/ds.asDataMatrix.R
+++ b/R/ds.asDataMatrix.R
@@ -55,15 +55,13 @@
 #' 
 ds.asDataMatrix <- function(x.name=NULL, newobj=NULL, datasources=NULL){
 
-  datasources <- .set_datasources(datasources)
+  datasources <- .resolveDatasources(datasources)
 
   if(is.null(x.name)){
     stop("Please provide the name of the input vector!", call.=FALSE)
   }
   
-  if(is.null(newobj)){
-    newobj <- "asdatamatrix.newobj"
-  }
+  newobj <- .resolveNewobjName(newobj, "asdatamatrix.newobj")
 
 	calltext <- call("asDataMatrixDS", x.name)
 	DSI::datashield.assign(datasources, newobj, calltext)
diff --git a/R/ds.asFactor.R b/R/ds.asFactor.R
index a8ae29f48..cbed01eec 100644
--- a/R/ds.asFactor.R
+++ b/R/ds.asFactor.R
@@ -188,7 +188,7 @@
 ds.asFactor <- function(input.var.name=NULL, newobj.name=NULL, forced.factor.levels=NULL, fixed.dummy.vars=FALSE,
                         baseline.level=1, datasources=NULL){
 
-  datasources <- .set_datasources(datasources)
+  datasources <- .resolveDatasources(datasources)
 
   # check if user has provided the name of the column that holds the input variable
   if(is.null(input.var.name)){
diff --git a/R/ds.asFactorSimple.R b/R/ds.asFactorSimple.R
index fc092d352..6ca510d42 100644
--- a/R/ds.asFactorSimple.R
+++ b/R/ds.asFactorSimple.R
@@ -24,7 +24,7 @@
 #'
 ds.asFactorSimple <- function(input.var.name=NULL, newobj.name=NULL, datasources=NULL){
 
-  datasources <- .set_datasources(datasources)
+  datasources <- .resolveDatasources(datasources)
 
   # check if user has provided the name of the column that holds the input variable
   if(is.null(input.var.name)){
diff --git a/R/ds.asInteger.R b/R/ds.asInteger.R
index bd5eb2921..8c5034519 100644
--- a/R/ds.asInteger.R
+++ b/R/ds.asInteger.R
@@ -69,15 +69,13 @@
 #' @export
 ds.asInteger <- function(x.name=NULL, newobj=NULL, datasources=NULL){
   
-  datasources <- .set_datasources(datasources)
+  datasources <- .resolveDatasources(datasources)
 
   if(is.null(x.name)){
     stop("Please provide the name of the input vector!", call.=FALSE)
   }
   
-  if(is.null(newobj)){
-    newobj <- "asinteger.newobj"
-  }
+  newobj <- .resolveNewobjName(newobj, "asinteger.newobj")
 
   calltext <- call("asIntegerDS", x.name)
   DSI::datashield.assign(datasources, newobj, calltext)
diff --git a/R/ds.asList.R b/R/ds.asList.R
index 516d51e39..29e1897a1 100644
--- a/R/ds.asList.R
+++ b/R/ds.asList.R
@@ -57,15 +57,13 @@
 #' 
 ds.asList <- function(x.name=NULL, newobj=NULL, datasources=NULL){
 
-  datasources <- .set_datasources(datasources)
+  datasources <- .resolveDatasources(datasources)
 
   if(is.null(x.name)){
     stop("Please provide the name of the input vector!", call.=FALSE)
   }
 
-  if(is.null(newobj)){
-    newobj <- "aslist.newobj"
-  }
+  newobj <- .resolveNewobjName(newobj, "aslist.newobj")
 
   datashield.assign(datasources, newobj, call("asListDS", x.name))
 
diff --git a/R/ds.asLogical.R b/R/ds.asLogical.R
index 89dfb2556..e8c59f6e6 100644
--- a/R/ds.asLogical.R
+++ b/R/ds.asLogical.R
@@ -56,15 +56,13 @@
 #' 
 ds.asLogical <- function(x.name=NULL, newobj=NULL, datasources=NULL){
 
-  datasources <- .set_datasources(datasources)
+  datasources <- .resolveDatasources(datasources)
 
   if(is.null(x.name)){
     stop("Please provide the name of the input vector!", call.=FALSE)
   }
   
-  if(is.null(newobj)){
-    newobj <- "aslogical.newobj"
-  }
+  newobj <- .resolveNewobjName(newobj, "aslogical.newobj")
 
 	calltext <- call("asLogicalDS", x.name)
 	DSI::datashield.assign(datasources, newobj, calltext)
diff --git a/R/ds.asMatrix.R b/R/ds.asMatrix.R
index 1c97dbf1b..8fbcb17fa 100644
--- a/R/ds.asMatrix.R
+++ b/R/ds.asMatrix.R
@@ -58,15 +58,13 @@
 #' 
 ds.asMatrix <- function(x.name=NULL, newobj=NULL, datasources=NULL){
 
-  datasources <- .set_datasources(datasources)
+  datasources <- .resolveDatasources(datasources)
 
   if(is.null(x.name)){
     stop("Please provide the name of the input vector!", call.=FALSE)
   }
   
-  if(is.null(newobj)){
-    newobj <- "asmatrix.newobj"
-  }
+  newobj <- .resolveNewobjName(newobj, "asmatrix.newobj")
 
 	calltext <- call("asMatrixDS", x.name)
 	DSI::datashield.assign(datasources, newobj, calltext)
diff --git a/R/ds.asNumeric.R b/R/ds.asNumeric.R
index 980a71176..656caa813 100644
--- a/R/ds.asNumeric.R
+++ b/R/ds.asNumeric.R
@@ -70,15 +70,13 @@
 #' 
 ds.asNumeric <- function(x.name=NULL, newobj=NULL, datasources=NULL){
 
-  datasources <- .set_datasources(datasources)
+  datasources <- .resolveDatasources(datasources)
 
   if(is.null(x.name)){
     stop("Please provide the name of the input vector!", call.=FALSE)
   }
   
-  if(is.null(newobj)){
-    newobj <- "asnumeric.newobj"
-  }
+  newobj <- .resolveNewobjName(newobj, "asnumeric.newobj")
 
   calltext <- call("asNumericDS", x.name)
   DSI::datashield.assign(datasources, newobj, calltext)
diff --git a/R/ds.assign.R b/R/ds.assign.R
index c646e3785..836761177 100644
--- a/R/ds.assign.R
+++ b/R/ds.assign.R
@@ -57,16 +57,14 @@
 #'
 ds.assign <- function(toAssign=NULL, newobj=NULL, datasources=NULL){
   
-  datasources <- .set_datasources(datasources)
+  datasources <- .resolveDatasources(datasources)
 
   if(is.null(toAssign)){
     stop("Please give the name of object to assign or an expression to evaluate and assign.!\n", call.=FALSE)
   }
 
   # create a name by default if user did not provide a name for the new variable
-  if(is.null(newobj)){
-    newobj <- "assign.newobj"
-  }
+  newobj <- .resolveNewobjName(newobj, "assign.newobj")
 
   # now do the business
   DSI::datashield.assign(datasources, newobj, as.symbol(toAssign))
diff --git a/R/ds.auc.R b/R/ds.auc.R
index 8b16502b1..e1c781480 100644
--- a/R/ds.auc.R
+++ b/R/ds.auc.R
@@ -16,7 +16,7 @@
 #'
 ds.auc <- function(pred=NULL, y=NULL, datasources=NULL){
   
-  datasources <- .set_datasources(datasources)
+  datasources <- .resolveDatasources(datasources)
   
   # verify that 'pred' was set
   if(is.null(pred)){
diff --git a/R/ds.boxPlot.R b/R/ds.boxPlot.R
index cb51d601f..c793e31fd 100644
--- a/R/ds.boxPlot.R
+++ b/R/ds.boxPlot.R
@@ -87,7 +87,7 @@
 ds.boxPlot <- function(x, variables = NULL, group = NULL, group2 = NULL, xlabel = "x axis", 
                        ylabel = "y axis", type = "pooled", datasources = NULL){
   
-  datasources <- .set_datasources(datasources)
+  datasources <- .resolveDatasources(datasources)
 
   # Ensure type is 'pooled' or 'split'
   if((length(type) == 1) && (! any(type %in% c("pooled", "split")))){
@@ -96,7 +96,7 @@ ds.boxPlot <- function(x, variables = NULL, group = NULL, group2 = NULL, xlabel
 
   # Determine class of x for dispatch
   cls <- datashield.aggregate(datasources, call("classDS", x))
-  .checkClassConsistency(lapply(cls, function(study.class) list(class = study.class)), object_name = x)
+  .checkClassConsistency(lapply(cls, function(study.class) list(class = study.class)), objectName = x)
   cls <- unique(unlist(cls))
 
   if(!any(c("numeric", "data.frame") %in% cls)){
diff --git a/R/ds.boxPlotGG.R b/R/ds.boxPlotGG.R
index e562d9719..590296fc3 100644
--- a/R/ds.boxPlotGG.R
+++ b/R/ds.boxPlotGG.R
@@ -24,7 +24,7 @@
 
 ds.boxPlotGG <- function(x, group = NULL, group2 = NULL, xlabel = "x axis", ylabel = "y axis", type = "pooled", datasources = NULL){
   x_var <- lower <- upper <- ymin <- ymax <- middle <- fill <- NULL
-  datasources <- .set_datasources(datasources)
+  datasources <- .resolveDatasources(datasources)
 
   plot_data <- datashield.aggregate(datasources, call("boxPlotGGDS", data_table.name=x, group=group, group2=group2))
 
diff --git a/R/ds.boxPlotGG_data_Treatment.R b/R/ds.boxPlotGG_data_Treatment.R
index 84d32e1ab..204d21a2b 100644
--- a/R/ds.boxPlotGG_data_Treatment.R
+++ b/R/ds.boxPlotGG_data_Treatment.R
@@ -20,7 +20,7 @@
 
 ds.boxPlotGG_data_Treatment <- function(table, variables, group = NULL, group2 = NULL, datasources = NULL){
   
-  datasources <- .set_datasources(datasources)
+  datasources <- .resolveDatasources(datasources)
 
   datashield.assign.expr(datasources, "boxPlotRawData", call("boxPlotGG_data_TreatmentDS", table.name = table, variables = variables, group = group, group2 = group2))
   
diff --git a/R/ds.boxPlotGG_data_Treatment_numeric.R b/R/ds.boxPlotGG_data_Treatment_numeric.R
index b80baca6d..066f1ca28 100644
--- a/R/ds.boxPlotGG_data_Treatment_numeric.R
+++ b/R/ds.boxPlotGG_data_Treatment_numeric.R
@@ -15,7 +15,7 @@
 
 ds.boxPlotGG_data_Treatment_numeric <- function(vector, datasources = NULL){
   
-  datasources <- .set_datasources(datasources)
+  datasources <- .resolveDatasources(datasources)
 
   datashield.assign.expr(datasources, "boxPlotRawDataNumeric", call("boxPlotGG_data_Treatment_numericDS", vector.name = vector))
   
diff --git a/R/ds.boxPlotGG_numeric.R b/R/ds.boxPlotGG_numeric.R
index e3d4a679f..c666c0f86 100644
--- a/R/ds.boxPlotGG_numeric.R
+++ b/R/ds.boxPlotGG_numeric.R
@@ -12,7 +12,7 @@
 
 ds.boxPlotGG_numeric <- function(x, xlabel = "x axis", ylabel = "y axis", type = "pooled", datasources = NULL){
   
-  datasources <- .set_datasources(datasources)
+  datasources <- .resolveDatasources(datasources)
 
   ds.boxPlotGG_data_Treatment_numeric(x, datasources)
   
diff --git a/R/ds.boxPlotGG_table.R b/R/ds.boxPlotGG_table.R
index 936caf769..667f00a86 100644
--- a/R/ds.boxPlotGG_table.R
+++ b/R/ds.boxPlotGG_table.R
@@ -18,7 +18,7 @@
 ds.boxPlotGG_table <- function(x, variables, group = NULL, group2 = NULL, xlabel = "x axis", 
                                ylabel = "y axis", type = "pooled", datasources = NULL){
   
-  datasources <- .set_datasources(datasources)
+  datasources <- .resolveDatasources(datasources)
 
   ds.boxPlotGG_data_Treatment(x, variables, group, group2, datasources)
   
diff --git a/R/ds.bp_standards.R b/R/ds.bp_standards.R
index fe9b69fa5..f01c1d981 100644
--- a/R/ds.bp_standards.R
+++ b/R/ds.bp_standards.R
@@ -32,7 +32,7 @@
 ds.bp_standards <- function(sex=NULL, age=NULL, height=NULL, bp=NULL, systolic=TRUE, 
                             newobj=NULL, datasources=NULL){
   
-  datasources <- .set_datasources(datasources)
+  datasources <- .resolveDatasources(datasources)
   
   # verify that 'sex' was set
   if(is.null(sex)){
@@ -55,9 +55,7 @@ ds.bp_standards <- function(sex=NULL, age=NULL, height=NULL, bp=NULL, systolic=T
   }
   
   # if no output object specified then provide a default name
-  if(is.null(newobj)){
-    newobj <- "bp.newobj"
-  }
+  newobj <- .resolveNewobjName(newobj, "bp.newobj")
   
   # call the server-side assign function
   cally <- call('bp_standardsDS', sex, age, height, bp, systolic)
diff --git a/R/ds.c.R b/R/ds.c.R
index 8a9284139..a6a21238d 100644
--- a/R/ds.c.R
+++ b/R/ds.c.R
@@ -60,16 +60,14 @@
 #'
 ds.c <- function(x=NULL, newobj=NULL, datasources=NULL, classConsistencyCheck=TRUE){
 
-  datasources <- .set_datasources(datasources)
+  datasources <- .resolveDatasources(datasources)
 
   if(is.null(x)){
     stop("x=NULL. Please provide the names of the objects to concatenate!", call.=FALSE)
   }
 
   # create a name by default if user did not provide a name for the new variable
-  if(is.null(newobj)){
-    newobj <- "c.newobj"
-  }
+  newobj <- .resolveNewobjName(newobj, "c.newobj")
 
   if(classConsistencyCheck){
     for(i in seq_along(x)){
diff --git a/R/ds.cbind.R b/R/ds.cbind.R
index 1af1737a1..2291eb507 100644
--- a/R/ds.cbind.R
+++ b/R/ds.cbind.R
@@ -117,7 +117,7 @@
 #'
 ds.cbind <- function(x=NULL, DataSHIELD.checks=FALSE, force.colnames=NULL, newobj=NULL, datasources=NULL, notify.of.progress=FALSE, classConsistencyCheck=TRUE){
 
-  datasources <- .set_datasources(datasources)
+  datasources <- .resolveDatasources(datasources)
 
   if(is.null(x)){
     stop("Please provide a vector of character strings holding the name of the input elements!", call.=FALSE)
@@ -174,9 +174,7 @@ ds.cbind <- function(x=NULL, DataSHIELD.checks=FALSE, force.colnames=NULL, newob
   }
   
   # check newobj not actively declared as null
-  if(is.null(newobj)){
-    newobj <- "cbind.newobj"
-  }
+  newobj <- .resolveNewobjName(newobj, "cbind.newobj")
   
   # CREATE THE VECTOR OF COLUMN NAMES
   colname.list <- list()
diff --git a/R/ds.changeRefGroup.R b/R/ds.changeRefGroup.R
index 2ce6136aa..1f1435e27 100644
--- a/R/ds.changeRefGroup.R
+++ b/R/ds.changeRefGroup.R
@@ -112,7 +112,7 @@
 #' @export
 ds.changeRefGroup <- function(x=NULL, ref=NULL, newobj=NULL, reorderByRef=FALSE, datasources=NULL){
 
-  datasources <- .set_datasources(datasources)
+  datasources <- .resolveDatasources(datasources)
 
   if(is.null(x)){
     stop("Please provide the name of a vector of type factor!", call.=FALSE)
@@ -123,9 +123,7 @@ ds.changeRefGroup <- function(x=NULL, ref=NULL, newobj=NULL, reorderByRef=FALSE,
   }
   
   # create a name by default if user did not provide a name for the new variable
-  if(is.null(newobj)){
-    newobj <- "changerefgroup.newobj"
-  }
+  newobj <- .resolveNewobjName(newobj, "changerefgroup.newobj")
 
   if(reorderByRef){
     warning("'reorderByRef' is set to TRUE. Please read the documentation for possible consequences!", call.=FALSE)
diff --git a/R/ds.class.R b/R/ds.class.R
index 299950a47..8d98f02b7 100644
--- a/R/ds.class.R
+++ b/R/ds.class.R
@@ -55,7 +55,7 @@
 #'
 ds.class <- function(x=NULL, datasources=NULL) {
 
-  datasources <- .set_datasources(datasources)
+  datasources <- .resolveDatasources(datasources)
 
   if(is.null(x)){
     stop("Please provide the name of the input object!", call.=FALSE)
diff --git a/R/ds.colnames.R b/R/ds.colnames.R
index 571574217..835c3a529 100644
--- a/R/ds.colnames.R
+++ b/R/ds.colnames.R
@@ -52,8 +52,8 @@
 #'
 ds.colnames <- function(x=NULL, datasources=NULL) {
 
-  datasources <- .set_datasources(datasources)
-  .check_df_name_provided(x)
+  datasources <- .resolveDatasources(datasources)
+  .checkDfNameProvided(x)
 
   cally <- call("colnamesDS", x)
   column_names <- DSI::datashield.aggregate(datasources, cally)
diff --git a/R/ds.completeCases.R b/R/ds.completeCases.R
index 1a3d3f5aa..acb7c52ec 100644
--- a/R/ds.completeCases.R
+++ b/R/ds.completeCases.R
@@ -73,15 +73,13 @@
 #' 
 ds.completeCases <- function(x1=NULL, newobj=NULL, datasources=NULL){
 
-  datasources <- .set_datasources(datasources)
+  datasources <- .resolveDatasources(datasources)
 
   if(is.null(x1)){
     return("Error: x1 must be a character string naming a serverside data.frame, matrix or vector")
   }
 
-  if(is.null(newobj)){
-    newobj <- paste0(x1,"_complete.cases")
-  }
+  newobj <- .resolveNewobjName(newobj, paste0(x1,"_complete.cases"))
 
   calltext <- call("completeCasesDS", x1)
   DSI::datashield.assign(datasources, newobj, calltext)
diff --git a/R/ds.contourPlot.R b/R/ds.contourPlot.R
index 94dfa21b0..dac0dbcb1 100644
--- a/R/ds.contourPlot.R
+++ b/R/ds.contourPlot.R
@@ -105,7 +105,7 @@
 #' 
 ds.contourPlot <- function(x=NULL, y=NULL, type='combine', show='all', numints=20, method="smallCellsRule", k=3, noise=0.25, datasources=NULL, classConsistencyCheck=FALSE){
 
-  datasources <- .set_datasources(datasources)
+  datasources <- .resolveDatasources(datasources)
 
   if(is.null(x)){
     stop("x=NULL. Please provide the names of two numeric vectors!", call.=FALSE)
@@ -145,8 +145,8 @@ ds.contourPlot <- function(x=NULL, y=NULL, type='combine', show='all', numints=2
     # call the server-side function that generates the x and y coordinates of the centroids
     anonymous.data <- datashield.aggregate(datasources, call("heatmapPlotDS", x.name=x, y.name=y, k=k, noise=noise, method.indicator=method.indicator))
     if(classConsistencyCheck){
-      .checkClassConsistency(anonymous.data, field = "class.x", object_name = x)
-      .checkClassConsistency(anonymous.data, field = "class.y", object_name = y)
+      .checkClassConsistency(anonymous.data, field = "class.x", objectName = x)
+      .checkClassConsistency(anonymous.data, field = "class.y", objectName = y)
     }
 
     pooled.points.x <- c()
@@ -164,8 +164,8 @@ ds.contourPlot <- function(x=NULL, y=NULL, type='combine', show='all', numints=2
     # call the server-side function that generates the x and y coordinates of the anonymous.data
     anonymous.data <- datashield.aggregate(datasources, call("heatmapPlotDS", x.name=x, y.name=y, k=k, noise=noise, method.indicator=method.indicator))
     if(classConsistencyCheck){
-      .checkClassConsistency(anonymous.data, field = "class.x", object_name = x)
-      .checkClassConsistency(anonymous.data, field = "class.y", object_name = y)
+      .checkClassConsistency(anonymous.data, field = "class.x", objectName = x)
+      .checkClassConsistency(anonymous.data, field = "class.y", objectName = y)
     }
 
     pooled.points.x <- c()
@@ -206,8 +206,8 @@ ds.contourPlot <- function(x=NULL, y=NULL, type='combine', show='all', numints=2
     # generate the grid density object to plot
     grid.density.obj <- datashield.aggregate(datasources, call("densityGridDS", x=x, y=y, limits=TRUE, x.min=x.global.min, x.max=x.global.max, y.min=y.global.min, y.max=y.global.max, numints=numints))
     if(classConsistencyCheck){
-      .checkClassConsistency(grid.density.obj, field = "class.x", object_name = x)
-      .checkClassConsistency(grid.density.obj, field = "class.y", object_name = y)
+      .checkClassConsistency(grid.density.obj, field = "class.x", objectName = x)
+      .checkClassConsistency(grid.density.obj, field = "class.y", objectName = y)
     }
     grid.density.obj <- lapply(grid.density.obj, function(r) r$grid)
 
@@ -361,8 +361,8 @@ ds.contourPlot <- function(x=NULL, y=NULL, type='combine', show='all', numints=2
      # generate the grid density object to plot
      grid.density.obj <- datashield.aggregate(datasources, call("densityGridDS", x=x, y=y, limits=FALSE, x.min=NULL, x.max=NULL, y.min=NULL, y.max=NULL, numints=numints))
      if(classConsistencyCheck){
-       .checkClassConsistency(grid.density.obj, field = "class.x", object_name = x)
-       .checkClassConsistency(grid.density.obj, field = "class.y", object_name = y)
+       .checkClassConsistency(grid.density.obj, field = "class.x", objectName = x)
+       .checkClassConsistency(grid.density.obj, field = "class.y", objectName = y)
      }
      grid.density.obj <- lapply(grid.density.obj, function(r) r$grid)
      numcol <- dim(grid.density.obj[[1]])[2]
diff --git a/R/ds.cor.R b/R/ds.cor.R
index 6043a5113..0e44b06d2 100644
--- a/R/ds.cor.R
+++ b/R/ds.cor.R
@@ -83,7 +83,7 @@
 #' 
 ds.cor <- function(x=NULL, y=NULL, type="split", datasources=NULL, classConsistencyCheck=TRUE){
 
-  datasources <- .set_datasources(datasources)
+  datasources <- .resolveDatasources(datasources)
 
   if(is.null(x)){
     stop("x=NULL. Please provide the name of a matrix or dataframe or the names of two numeric vectors!", call.=FALSE)
diff --git a/R/ds.corTest.R b/R/ds.corTest.R
index 78c802168..609ce6d71 100644
--- a/R/ds.corTest.R
+++ b/R/ds.corTest.R
@@ -67,7 +67,7 @@
 #'
 ds.corTest <- function(x=NULL, y=NULL, method="pearson", exact=NULL, conf.level=0.95, type='split', datasources=NULL, classConsistencyCheck=FALSE){
 
-  datasources <- .set_datasources(datasources)
+  datasources <- .resolveDatasources(datasources)
 
   if(is.null(x)){
     stop("x=NULL. Please provide the names of the 1st numeric vector!", call.=FALSE)
diff --git a/R/ds.cov.R b/R/ds.cov.R
index a35c9097a..a7ffac52c 100644
--- a/R/ds.cov.R
+++ b/R/ds.cov.R
@@ -100,7 +100,7 @@
 #'
 ds.cov <- function(x=NULL, y=NULL, naAction='pairwise.complete', type="split", datasources=NULL, classConsistencyCheck=TRUE){
 
-  datasources <- .set_datasources(datasources)
+  datasources <- .resolveDatasources(datasources)
 
   if(is.null(x)){
     stop("x=NULL. Please provide the name of a matrix or dataframe or the names of two numeric vectors!", call.=FALSE)
diff --git a/R/ds.dataFrame.R b/R/ds.dataFrame.R
index c06322a50..c3aea4fb2 100644
--- a/R/ds.dataFrame.R
+++ b/R/ds.dataFrame.R
@@ -92,16 +92,14 @@
 #' @export
 ds.dataFrame <- function(x=NULL, row.names=NULL, check.rows=FALSE, check.names=TRUE, stringsAsFactors=TRUE, completeCases=FALSE, DataSHIELD.checks=FALSE, newobj=NULL, datasources=NULL, notify.of.progress=FALSE, classConsistencyCheck=TRUE){
 
-  datasources <- .set_datasources(datasources)
+  datasources <- .resolveDatasources(datasources)
 
   if(is.null(x)){
     stop("Please provide the name of the list that holds the input vectors!", call.=FALSE)
   }
 
   # create a name by default if user did not provide a name for the new variable
-  if(is.null(newobj)){
-    newobj <- "dataframe.newobj"
-  }
+  newobj <- .resolveNewobjName(newobj, "dataframe.newobj")
 
   if(DataSHIELD.checks){
 
@@ -154,9 +152,7 @@ ds.dataFrame <- function(x=NULL, row.names=NULL, check.rows=FALSE, check.names=T
   }
   
   # check newobj not actively declared as null
-  if(is.null(newobj)){
-    newobj <- "df_new"
-  }
+  newobj <- .resolveNewobjName(newobj, "df_new")
 
   # CREATE THE VECTOR OF COLUMN NAMES
   colname.list <- list()
diff --git a/R/ds.dataFrameSort.R b/R/ds.dataFrameSort.R
index 3e41eccdd..df807c51b 100644
--- a/R/ds.dataFrameSort.R
+++ b/R/ds.dataFrameSort.R
@@ -83,7 +83,7 @@
 ds.dataFrameSort<-function(df.name=NULL, sort.key.name=NULL, sort.descending=FALSE,
                            sort.method="default", newobj=NULL, datasources=NULL){
 
-  datasources <- .set_datasources(datasources)
+  datasources <- .resolveDatasources(datasources)
 
   if(is.null(sort.method)){
     sort.method <- "default"
@@ -105,7 +105,7 @@ ds.dataFrameSort<-function(df.name=NULL, sort.key.name=NULL, sort.descending=FAL
     sort.descending <- FALSE
   }
   
-  newobj <- .set_newobj_name(newobj, "dataframesort.newobj")
+  newobj <- .resolveNewobjName(newobj, "dataframesort.newobj")
   
   # Call to assign function
   calltext <- call("dataFrameSortDS", df.name, sort.key.name, sort.descending, sort.method)
diff --git a/R/ds.dataFrameSubset.R b/R/ds.dataFrameSubset.R
index c6603c41c..46af4e411 100644
--- a/R/ds.dataFrameSubset.R
+++ b/R/ds.dataFrameSubset.R
@@ -107,7 +107,7 @@
 
 ds.dataFrameSubset<-function(df.name=NULL, V1.name=NULL, V2.name=NULL, Boolean.operator=NULL, keep.cols=NULL, rm.cols=NULL, keep.NAs=NULL, newobj=NULL, datasources=NULL, notify.of.progress=FALSE){
 
-  datasources <- .set_datasources(datasources)
+  datasources <- .resolveDatasources(datasources)
 
   # check if user has provided the name of the data.frame to be subsetted
   if(is.null(df.name)){
@@ -197,9 +197,7 @@ if(Boolean.operator == ">="){
 }
 
   # if no value spcified for output object, then specify a default
-  if(is.null(newobj)){
-    newobj <- "dataframesubset.newobj"
-  }
+  newobj <- .resolveNewobjName(newobj, "dataframesubset.newobj")
 
  if(!is.null(keep.cols)){
   keep.cols<-paste0(as.character(keep.cols),collapse=",")
diff --git a/R/ds.densityGrid.R b/R/ds.densityGrid.R
index e2dcae6c1..965c5cfb2 100644
--- a/R/ds.densityGrid.R
+++ b/R/ds.densityGrid.R
@@ -86,7 +86,7 @@
 #'
 ds.densityGrid <- function(x=NULL, y=NULL, numints=20, type='combine', datasources=NULL, classConsistencyCheck=FALSE){
 
-  datasources <- .set_datasources(datasources)
+  datasources <- .resolveDatasources(datasources)
 
   if(is.null(x)){
     stop("Please provide the name of the numeric vector 'x'!", call.=FALSE)
@@ -129,8 +129,8 @@ ds.densityGrid <- function(x=NULL, y=NULL, numints=20, type='combine', datasourc
     # generate the grid density object to plot
     grid.density.obj <- datashield.aggregate(datasources, call("densityGridDS", x=x, y=y, limits=TRUE, x.min=x.global.min, x.max=x.global.max, y.min=y.global.min, y.max=y.global.max, numints=numints))
     if(classConsistencyCheck){
-      .checkClassConsistency(grid.density.obj, field = "class.x", object_name = x)
-      .checkClassConsistency(grid.density.obj, field = "class.y", object_name = y)
+      .checkClassConsistency(grid.density.obj, field = "class.x", objectName = x)
+      .checkClassConsistency(grid.density.obj, field = "class.y", objectName = y)
     }
     grid.density.obj <- lapply(grid.density.obj, function(r) r$grid)
     numcol <- dim(grid.density.obj[[1]])[2]
@@ -153,8 +153,8 @@ ds.densityGrid <- function(x=NULL, y=NULL, numints=20, type='combine', datasourc
       # generate the grid density object
       grid.density.obj <- datashield.aggregate(datasources, call("densityGridDS", x=x, y=y, limits=FALSE, x.min=NULL, x.max=NULL, y.min=NULL, y.max=NULL, numints=numints))
       if(classConsistencyCheck){
-        .checkClassConsistency(grid.density.obj, field = "class.x", object_name = x)
-        .checkClassConsistency(grid.density.obj, field = "class.y", object_name = y)
+        .checkClassConsistency(grid.density.obj, field = "class.x", objectName = x)
+        .checkClassConsistency(grid.density.obj, field = "class.y", objectName = y)
       }
       grid.density.obj <- lapply(grid.density.obj, function(r) r$grid)
       numcol <- dim(grid.density.obj[[1]])[2]
diff --git a/R/ds.dim.R b/R/ds.dim.R
index efafd5862..3d309e75c 100644
--- a/R/ds.dim.R
+++ b/R/ds.dim.R
@@ -80,7 +80,7 @@
 #'
 ds.dim <- function(x=NULL, type='both', datasources=NULL, classConsistencyCheck=TRUE) {
 
-  datasources <- .set_datasources(datasources)
+  datasources <- .resolveDatasources(datasources)
 
   if(is.null(x)){
     stop("Please provide the name of a data.frame or matrix!", call.=FALSE)
diff --git a/R/ds.dmtC2S.R b/R/ds.dmtC2S.R
index 96d059e61..f5ec7354c 100644
--- a/R/ds.dmtC2S.R
+++ b/R/ds.dmtC2S.R
@@ -46,7 +46,7 @@
 #'
 ds.dmtC2S <- function(dfdata=NA, newobj=NULL, datasources=NULL){
 
-  datasources <- .set_datasources(datasources)
+  datasources <- .resolveDatasources(datasources)
 
   # check if a value has been provided for dfdata
   if(is.null(dfdata)){
@@ -54,9 +54,7 @@ ds.dmtC2S <- function(dfdata=NA, newobj=NULL, datasources=NULL){
   }
 
   # if no value specified for output object, then specify a default
-  if(is.null(newobj)){
-    newobj <- "dmt.copied.C2S"
-  }
+  newobj <- .resolveNewobjName(newobj, "dmt.copied.C2S")
 
 #Generate values for arguments reflecting the key characteristics of the
 #clientside matrix/data frame to be copied to the serverside
diff --git a/R/ds.elspline.R b/R/ds.elspline.R
index 40a77db4d..b96d8c317 100644
--- a/R/ds.elspline.R
+++ b/R/ds.elspline.R
@@ -28,7 +28,7 @@
 #'
 ds.elspline <- function(x, n, marginal = FALSE, names = NULL, newobj = NULL, datasources = NULL){
   
-  datasources <- .set_datasources(datasources)
+  datasources <- .resolveDatasources(datasources)
   
   if(is.null(x)){
     stop("Please provide the name of the input variable x!", call.=FALSE)
@@ -43,9 +43,7 @@ ds.elspline <- function(x, n, marginal = FALSE, names = NULL, newobj = NULL, dat
   }
   
   # create a name by default if user did not provide a name for the new variable
-  if(is.null(newobj)){
-    newobj <- "elspline.newobj"
-  }
+  newobj <- .resolveNewobjName(newobj, "elspline.newobj")
   
   # now do the business
   calltext <- call("elsplineDS", x, n, marginal, names)
diff --git a/R/ds.exists.R b/R/ds.exists.R
index b7a378144..e8e809284 100644
--- a/R/ds.exists.R
+++ b/R/ds.exists.R
@@ -62,7 +62,7 @@
 #'
 ds.exists <- function(x=NULL, datasources=NULL){
 
-  datasources <- .set_datasources(datasources)
+  datasources <- .resolveDatasources(datasources)
 
   if(is.null(x)){
     stop("Please provide the name of the input object!", call.=FALSE)
diff --git a/R/ds.exp.R b/R/ds.exp.R
index c23fbaba4..6ab41780c 100644
--- a/R/ds.exp.R
+++ b/R/ds.exp.R
@@ -58,15 +58,13 @@
 #'
 ds.exp <- function(x=NULL, newobj=NULL, datasources=NULL){
 
-  datasources <- .set_datasources(datasources)
+  datasources <- .resolveDatasources(datasources)
 
   if(is.null(x)){
     stop("Please provide the name of the input object!", call.=FALSE)
   }
 
-  if(is.null(newobj)){
-    newobj <- "exp.newobj"
-  }
+  newobj <- .resolveNewobjName(newobj, "exp.newobj")
 
   cally <- call("expDS", x)
   DSI::datashield.assign(datasources, newobj, cally)
diff --git a/R/ds.gamlss.R b/R/ds.gamlss.R
index 4a0d040ed..6a9dd0938 100644
--- a/R/ds.gamlss.R
+++ b/R/ds.gamlss.R
@@ -82,7 +82,7 @@ ds.gamlss <- function(formula = NULL, sigma.formula = '~1', nu.formula = '~1',
                       i.control = c(0.001, 50, 30, 0.001), centiles = FALSE, 
                       xvar = NULL, newobj = NULL, datasources = NULL){
   
-  datasources <- .set_datasources(datasources)
+  datasources <- .resolveDatasources(datasources)
 
   # verify that 'formula' was set
   if(is.null(formula)){
@@ -158,9 +158,7 @@ ds.gamlss <- function(formula = NULL, sigma.formula = '~1', nu.formula = '~1',
     stop("Provide the name of the explanatory variable in 'xvar' argument", call.=FALSE)
   }
   
-  if(is.null(newobj)){
-    newobj <- 'gamlss_res'
-  }
+  newobj <- .resolveNewobjName(newobj, 'gamlss_res')
   
   calltext <- call('gamlssDS', formula=formula, sigma.formula=sigma.formula, 
                    nu.formula=nu.formula, tau.formula=tau.formula,
diff --git a/R/ds.getWGSR.R b/R/ds.getWGSR.R
index f7fa79e36..a95dd55c1 100644
--- a/R/ds.getWGSR.R
+++ b/R/ds.getWGSR.R
@@ -103,7 +103,7 @@
 #'
 ds.getWGSR <- function(sex=NULL, firstPart=NULL, secondPart=NULL, index=NULL, standing=NA, thirdPart=NA, newobj=NULL, datasources=NULL){
   
-  datasources <- .set_datasources(datasources)
+  datasources <- .resolveDatasources(datasources)
 
   if(is.null(sex)){
     stop("Please provide the column name of the 'sex' variable!", call.=FALSE)
@@ -132,9 +132,7 @@ ds.getWGSR <- function(sex=NULL, firstPart=NULL, secondPart=NULL, index=NULL, st
   }
   
   # check newobj not actively declared as null
-  if(is.null(newobj)){
-    newobj <- "getWGSR.newobj"
-  }
+  newobj <- .resolveNewobjName(newobj, "getWGSR.newobj")
   
   cally <- call("getWGSRDS", sex, firstPart, secondPart, index, standing, thirdPart)
   DSI::datashield.assign(datasources, newobj, cally)
diff --git a/R/ds.glm.R b/R/ds.glm.R
index d69377950..6d9be8d9d 100644
--- a/R/ds.glm.R
+++ b/R/ds.glm.R
@@ -322,7 +322,7 @@
 ds.glm <- function(formula=NULL, data=NULL, family=NULL, offset=NULL, weights=NULL, checks=FALSE, maxit=20, CI=0.95,
                      viewIter=FALSE, viewVarCov=FALSE, viewCor=FALSE, datasources=NULL){
 
-  datasources <- .set_datasources(datasources)
+  datasources <- .resolveDatasources(datasources)
 
   # verify that 'formula' was set
   if(is.null(formula)){
diff --git a/R/ds.glmPredict.R b/R/ds.glmPredict.R
index e7e0c02ac..820d0ff51 100644
--- a/R/ds.glmPredict.R
+++ b/R/ds.glmPredict.R
@@ -128,7 +128,7 @@ ds.glmPredict <- function(glmname = NULL, newdataname = NULL, output.type = "res
                           se.fit = FALSE, dispersion = NULL, terms = NULL,
                           na.action = "na.pass", newobj = NULL, datasources = NULL){
 
-  datasources <- .set_datasources(datasources)
+  datasources <- .resolveDatasources(datasources)
 
   # check that <glmname> is set
   if(is.null(glmname)){
@@ -146,9 +146,7 @@ ds.glmPredict <- function(glmname = NULL, newdataname = NULL, output.type = "res
   }
 
   # provide value for newobj if none specified
-  if(is.null(newobj)){
-    newobj<-"predict_glm"
-  }
+  newobj <- .resolveNewobjName(newobj, "predict_glm")
 
   calltext <- call("glmPredictDS.as", glmname, newdataname, output.type, se.fit, dispersion, terms, na.action)
   DSI::datashield.assign(datasources, newobj, calltext)
diff --git a/R/ds.glmSLMA.R b/R/ds.glmSLMA.R
index b86271248..62d1b278c 100644
--- a/R/ds.glmSLMA.R
+++ b/R/ds.glmSLMA.R
@@ -370,7 +370,7 @@
 ds.glmSLMA<-function(formula=NULL, family=NULL, offset=NULL, weights=NULL, combine.with.metafor=TRUE,
 	newobj=NULL,dataName=NULL,checks=FALSE, maxit=30, notify.of.progress=FALSE, datasources=NULL) {
 
-  datasources <- .set_datasources(datasources)
+  datasources <- .resolveDatasources(datasources)
 
   # verify that 'formula' was set
   if(is.null(formula)){
@@ -591,9 +591,7 @@ if(at.least.one.study.data.error)
 #OBJECT ON SERVERSIDE
 
 # if no value specified for glm output object, then specify a default
-		if(is.null(newobj)){
-		newobj <- "new.glm.obj"
-		}
+		newobj <- .resolveNewobjName(newobj, "new.glm.obj")
 
    if (notify.of.progress) {
        message("\n\nSAVING SERVERSIDE glm OBJECT AS: <",newobj,">\n\n")
diff --git a/R/ds.glmSummary.R b/R/ds.glmSummary.R
index 077475847..401c16be1 100644
--- a/R/ds.glmSummary.R
+++ b/R/ds.glmSummary.R
@@ -79,7 +79,7 @@
 #'
 ds.glmSummary <- function(x.name, newobj=NULL, datasources=NULL) {
 
-  datasources <- .set_datasources(datasources)
+  datasources <- .resolveDatasources(datasources)
 
   # check if a value has been provided for x
   if(is.null(x.name)||!is.character(x.name)){
@@ -87,9 +87,7 @@ ds.glmSummary <- function(x.name, newobj=NULL, datasources=NULL) {
   }
 
   # create a name by default if the user did not provide a name for the new object
-  if (is.null(newobj)) {
-	  newobj <- "summary_glm.newobj"
-  }
+  newobj <- .resolveNewobjName(newobj, "summary_glm.newobj")
   
   # PREPARE AND CALL THE ASSIGN FUNCTION TO PREPARE THE summary_glm OBJECT ON THE SERVERSIDE
 	calltext1 <- call("glmSummaryDS.as", x.name)
diff --git a/R/ds.glmerSLMA.R b/R/ds.glmerSLMA.R
index ed254a081..f9d84c839 100644
--- a/R/ds.glmerSLMA.R
+++ b/R/ds.glmerSLMA.R
@@ -247,7 +247,7 @@ ds.glmerSLMA <- function(formula=NULL, offset=NULL, weights=NULL, combine.with.m
                        start_theta = NULL, start_fixef = NULL, notify.of.progress=FALSE, 
                        assign=FALSE, newobj=NULL){
   
-  datasources <- .set_datasources(datasources)
+  datasources <- .resolveDatasources(datasources)
 
   # verify that 'formula' was set
   if(is.null(formula)){
@@ -342,9 +342,7 @@ ds.glmerSLMA <- function(formula=NULL, offset=NULL, weights=NULL, combine.with.m
   
   if(assign==TRUE){
     
-    if(is.null(newobj)){
-      newobj <- "new.glmer.obj"
-    }
+    newobj <- .resolveNewobjName(newobj, "new.glmer.obj")
     
     
     if (notify.of.progress) {
diff --git a/R/ds.heatmapPlot.R b/R/ds.heatmapPlot.R
index 33d402aa4..85369097f 100644
--- a/R/ds.heatmapPlot.R
+++ b/R/ds.heatmapPlot.R
@@ -153,7 +153,7 @@
 ds.heatmapPlot <- function(x=NULL, y=NULL, type="combine", show="all", numints=20, 
                            method="smallCellsRule", k=3, noise=0.25, datasources=NULL, classConsistencyCheck=FALSE){
 
-  datasources <- .set_datasources(datasources)
+  datasources <- .resolveDatasources(datasources)
 
   if(is.null(x)){
     stop("x=NULL. Please provide the names of the 1st numeric vector!", call.=FALSE)
@@ -193,8 +193,8 @@ ds.heatmapPlot <- function(x=NULL, y=NULL, type="combine", show="all", numints=2
     # call the server-side function that generates the x and y coordinates of the centroids
     anonymous.data <- datashield.aggregate(datasources, call("heatmapPlotDS", x.name=x, y.name=y, k=k, noise=noise, method.indicator=method.indicator))
     if(classConsistencyCheck){
-      .checkClassConsistency(anonymous.data, field = "class.x", object_name = x)
-      .checkClassConsistency(anonymous.data, field = "class.y", object_name = y)
+      .checkClassConsistency(anonymous.data, field = "class.x", objectName = x)
+      .checkClassConsistency(anonymous.data, field = "class.y", objectName = y)
     }
 
     pooled.points.x <- c()
@@ -212,8 +212,8 @@ ds.heatmapPlot <- function(x=NULL, y=NULL, type="combine", show="all", numints=2
     # call the server-side function that generates the x and y coordinates of the anonymous.data
     anonymous.data <- datashield.aggregate(datasources, call("heatmapPlotDS", x.name=x, y.name=y, k=k, noise=noise, method.indicator=method.indicator))
     if(classConsistencyCheck){
-      .checkClassConsistency(anonymous.data, field = "class.x", object_name = x)
-      .checkClassConsistency(anonymous.data, field = "class.y", object_name = y)
+      .checkClassConsistency(anonymous.data, field = "class.x", objectName = x)
+      .checkClassConsistency(anonymous.data, field = "class.y", objectName = y)
     }
 
     pooled.points.x <- c()
@@ -254,8 +254,8 @@ ds.heatmapPlot <- function(x=NULL, y=NULL, type="combine", show="all", numints=2
       # generate the grid density object to plot
       grid.density.obj <- datashield.aggregate(datasources, call("densityGridDS", x=x, y=y, limits=TRUE, x.min=x.global.min, x.max=x.global.max, y.min=y.global.min, y.max=y.global.max, numints=numints))
       if(classConsistencyCheck){
-        .checkClassConsistency(grid.density.obj, field = "class.x", object_name = x)
-        .checkClassConsistency(grid.density.obj, field = "class.y", object_name = y)
+        .checkClassConsistency(grid.density.obj, field = "class.x", objectName = x)
+        .checkClassConsistency(grid.density.obj, field = "class.y", objectName = y)
       }
       grid.density.obj <- lapply(grid.density.obj, function(r) r$grid)
 
@@ -413,8 +413,8 @@ ds.heatmapPlot <- function(x=NULL, y=NULL, type="combine", show="all", numints=2
      # generate the grid density object to plot
      grid.density.obj <- datashield.aggregate(datasources, call("densityGridDS", x=x, y=y, limits=FALSE, x.min=NULL, x.max=NULL, y.min=NULL, y.max=NULL, numints=numints))
      if(classConsistencyCheck){
-       .checkClassConsistency(grid.density.obj, field = "class.x", object_name = x)
-       .checkClassConsistency(grid.density.obj, field = "class.y", object_name = y)
+       .checkClassConsistency(grid.density.obj, field = "class.x", objectName = x)
+       .checkClassConsistency(grid.density.obj, field = "class.y", objectName = y)
      }
      grid.density.obj <- lapply(grid.density.obj, function(r) r$grid)
 
diff --git a/R/ds.hetcor.R b/R/ds.hetcor.R
index 0a47676a3..be3e3f790 100644
--- a/R/ds.hetcor.R
+++ b/R/ds.hetcor.R
@@ -32,7 +32,7 @@
 #' 
 ds.hetcor <- function(data=NULL, ML=TRUE, std.err=TRUE, bins=4, pd=TRUE, use="complete.obs", datasources=NULL){
   
-  datasources <- .set_datasources(datasources)
+  datasources <- .resolveDatasources(datasources)
   
   if(is.null(data)){
     stop("Please provide the name of the input object!", call.=FALSE)
diff --git a/R/ds.histogram.R b/R/ds.histogram.R
index d0f4a7f31..611f8dcd6 100644
--- a/R/ds.histogram.R
+++ b/R/ds.histogram.R
@@ -155,7 +155,7 @@
 #'
 ds.histogram <- function(x=NULL, type="split", num.breaks=10, method="smallCellsRule", k=3, noise=0.25, vertical.axis="Frequency", datasources=NULL, classConsistencyCheck=FALSE){
 
-  datasources <- .set_datasources(datasources)
+  datasources <- .resolveDatasources(datasources)
 
   if(is.null(x)){
     stop("Please provide the name of the input vector!", call.=FALSE)
@@ -188,7 +188,7 @@ ds.histogram <- function(x=NULL, type="split", num.breaks=10, method="smallCells
   # call the server-side function that returns the range of the vector from each study
   histogram.ranges <- datashield.aggregate(datasources, call("histogramDS1", x=x, method.indicator=method.indicator, k=k, noise=noise))
   if(classConsistencyCheck){
-    .checkClassConsistency(histogram.ranges, object_name = x)
+    .checkClassConsistency(histogram.ranges, objectName = x)
   }
   ranges <- unique(unlist(lapply(histogram.ranges, function(r) r$range)))
 
diff --git a/R/ds.igb_standards.R b/R/ds.igb_standards.R
index dd4023045..5213bb811 100644
--- a/R/ds.igb_standards.R
+++ b/R/ds.igb_standards.R
@@ -42,7 +42,7 @@
 ds.igb_standards <- function(gagebrth=NULL, z=0, p=50, val=NULL, var=NULL, sex=NULL, 
                              fun='igb_value2zscore', newobj=NULL, datasources=NULL){
   
-  datasources <- .set_datasources(datasources)
+  datasources <- .resolveDatasources(datasources)
   
   # check if user has provided the name of the input variables
   if(is.null(gagebrth)){
@@ -70,9 +70,7 @@ ds.igb_standards <- function(gagebrth=NULL, z=0, p=50, val=NULL, var=NULL, sex=N
   }
   
   # if no output variable specified then provide a default name
-  if(is.null(newobj)){
-    newobj <- "igb.newobj"
-  }
+  newobj <- .resolveNewobjName(newobj, "igb.newobj")
   
   # call the server-side assign function
   cally <-  call('igb_standardsDS', gagebrth, z, p, val, var, sex, fun)
diff --git a/R/ds.isNA.R b/R/ds.isNA.R
index 63ef26586..2c4cf51ff 100644
--- a/R/ds.isNA.R
+++ b/R/ds.isNA.R
@@ -59,7 +59,7 @@
 #'
 ds.isNA <- function(x=NULL, datasources=NULL, classConsistencyCheck=TRUE){
 
-  datasources <- .set_datasources(datasources)
+  datasources <- .resolveDatasources(datasources)
 
   if(is.null(x)){
     stop("Please provide the name of the input vector!", call.=FALSE)
diff --git a/R/ds.isValid.R b/R/ds.isValid.R
index da48891ca..3ad72526c 100644
--- a/R/ds.isValid.R
+++ b/R/ds.isValid.R
@@ -59,7 +59,7 @@
 #'
 ds.isValid <- function(x=NULL, datasources=NULL, classConsistencyCheck=TRUE){
 
-  datasources <- .set_datasources(datasources)
+  datasources <- .resolveDatasources(datasources)
 
   if(is.null(x)){
     stop("Please provide the name of the input vector!", call.=FALSE)
diff --git a/R/ds.kurtosis.R b/R/ds.kurtosis.R
index 775f14d81..35ddfe78e 100644
--- a/R/ds.kurtosis.R
+++ b/R/ds.kurtosis.R
@@ -29,7 +29,7 @@
 #' 
 ds.kurtosis <- function(x=NULL, method=1, type='both', datasources=NULL, classConsistencyCheck=FALSE){
 
-  datasources <- .set_datasources(datasources)
+  datasources <- .resolveDatasources(datasources)
 
   if(is.null(x)){
     stop("Please provide the name of the input vector!", call.=FALSE)
diff --git a/R/ds.length.R b/R/ds.length.R
index 5db7d1e37..74cec9f5e 100644
--- a/R/ds.length.R
+++ b/R/ds.length.R
@@ -75,7 +75,7 @@
 #'
 ds.length <- function(x=NULL, type='both', datasources=NULL, classConsistencyCheck=TRUE){
 
-  datasources <- .set_datasources(datasources)
+  datasources <- .resolveDatasources(datasources)
 
   if(is.null(x)){
     stop("Please provide the name of the input object!", call.=FALSE)
diff --git a/R/ds.levels.R b/R/ds.levels.R
index 337a27591..8232f601f 100644
--- a/R/ds.levels.R
+++ b/R/ds.levels.R
@@ -59,7 +59,7 @@
 #'
 ds.levels <- function(x=NULL, datasources=NULL){
 
-  datasources <- .set_datasources(datasources)
+  datasources <- .resolveDatasources(datasources)
 
   if(is.null(x)){
     stop("Please provide the name of the input vector!", call.=FALSE)
diff --git a/R/ds.lexis.R b/R/ds.lexis.R
index fc0532c4f..2ae033685 100644
--- a/R/ds.lexis.R
+++ b/R/ds.lexis.R
@@ -203,7 +203,7 @@
 #'
 ds.lexis<-function(data=NULL, intervalWidth=NULL, idCol=NULL, entryCol=NULL, exitCol=NULL, statusCol=NULL, variables=NULL, expandDF=NULL, datasources=NULL){
 
-  datasources <- .set_datasources(datasources)
+  datasources <- .resolveDatasources(datasources)
 
   # check if user have provided the name of the column that holds the subject ids
   if(is.null(idCol)){
diff --git a/R/ds.list.R b/R/ds.list.R
index 3ec7707b8..9209291d7 100644
--- a/R/ds.list.R
+++ b/R/ds.list.R
@@ -56,16 +56,14 @@
 #'
 ds.list <- function(x=NULL, newobj=NULL, datasources=NULL, classConsistencyCheck=TRUE){
 
-  datasources <- .set_datasources(datasources)
+  datasources <- .resolveDatasources(datasources)
 
   if(is.null(x)){
     stop("x=NULL. Please provide the names of the objects to coerce into a list!", call.=FALSE)
   }
 
   # create a name by default if user did not provide a name for the new variable
-  if(is.null(newobj)){
-    newobj <- "list.newobj"
-  }
+  newobj <- .resolveNewobjName(newobj, "list.newobj")
 
   # get the variable names
   xnames <- extract(x)
diff --git a/R/ds.listDisclosureSettings.R b/R/ds.listDisclosureSettings.R
index f115bdb28..af0350f17 100644
--- a/R/ds.listDisclosureSettings.R
+++ b/R/ds.listDisclosureSettings.R
@@ -101,7 +101,7 @@
 #' }
 #'
 ds.listDisclosureSettings <- function(datasources=NULL){
-  datasources <- .set_datasources(datasources)
+  datasources <- .resolveDatasources(datasources)
 
   # CALL THE MAIN SERVER SIDE FUNCTION
   calltext <- call("listDisclosureSettingsDS")
diff --git a/R/ds.lmerSLMA.R b/R/ds.lmerSLMA.R
index 3f0f5cfc0..400160a1f 100644
--- a/R/ds.lmerSLMA.R
+++ b/R/ds.lmerSLMA.R
@@ -206,7 +206,7 @@ ds.lmerSLMA <- function(formula=NULL, offset=NULL, weights=NULL, combine.with.me
                       control_value = NULL, optimizer = NULL, verbose = 0, notify.of.progress=FALSE,
                       assign=FALSE, newobj=NULL){
 
-  datasources <- .set_datasources(datasources)
+  datasources <- .resolveDatasources(datasources)
 
   # verify that 'formula' was set
   if(is.null(formula)){
@@ -286,9 +286,7 @@ ds.lmerSLMA <- function(formula=NULL, offset=NULL, weights=NULL, combine.with.me
   
   if(assign==TRUE){
     
-    if(is.null(newobj)){
-      newobj <- "new.lmer.obj"
-    }
+    newobj <- .resolveNewobjName(newobj, "new.lmer.obj")
     
     if (notify.of.progress) {
         message("\n\nSAVING SERVERSIDE lmerMod OBJECT AS: <",newobj,">\n\n")
diff --git a/R/ds.log.R b/R/ds.log.R
index ca2364619..145ec93e5 100644
--- a/R/ds.log.R
+++ b/R/ds.log.R
@@ -58,15 +58,13 @@
 #'
 ds.log <- function(x=NULL, base=exp(1), newobj=NULL, datasources=NULL){
 
-  datasources <- .set_datasources(datasources)
+  datasources <- .resolveDatasources(datasources)
 
   if(is.null(x)){
     stop("Please provide the name of the input vector!", call.=FALSE)
   }
 
-  if(is.null(newobj)){
-    newobj <- "log.newobj"
-  }
+  newobj <- .resolveNewobjName(newobj, "log.newobj")
 
   cally <- call("logDS", x, base)
   DSI::datashield.assign(datasources, newobj, cally)
diff --git a/R/ds.ls.R b/R/ds.ls.R
index 7377d59ec..4df9ad677 100644
--- a/R/ds.ls.R
+++ b/R/ds.ls.R
@@ -119,7 +119,7 @@
 #' @export
 ds.ls <- function(search.filter=NULL, env.to.search=1L, search.GlobalEnv=TRUE, datasources=NULL){
 
-  datasources <- .set_datasources(datasources)
+  datasources <- .resolveDatasources(datasources)
 
   # make default to .GlobalEnv unambiguous
   if(search.GlobalEnv||is.null(env.to.search)){
diff --git a/R/ds.lspline.R b/R/ds.lspline.R
index 2fe8471ba..1cfc3cd8f 100644
--- a/R/ds.lspline.R
+++ b/R/ds.lspline.R
@@ -25,7 +25,7 @@
 #'
 ds.lspline <- function(x, knots = NULL, marginal = FALSE, names = NULL, newobj = NULL, datasources = NULL){
   
-  datasources <- .set_datasources(datasources)
+  datasources <- .resolveDatasources(datasources)
   
   if(is.null(x)){
     stop("Please provide the name of the input variable x!", call.=FALSE)
@@ -36,9 +36,7 @@ ds.lspline <- function(x, knots = NULL, marginal = FALSE, names = NULL, newobj =
   }
   
   # create a name by default if user did not provide a name for the new variable
-  if(is.null(newobj)){
-    newobj <- "lspline.newobj"
-  }
+  newobj <- .resolveNewobjName(newobj, "lspline.newobj")
   
   # now do the business
   calltext <- call("lsplineDS", x, knots, marginal, names)
diff --git a/R/ds.make.R b/R/ds.make.R
index 2e9cbea58..e469087c1 100644
--- a/R/ds.make.R
+++ b/R/ds.make.R
@@ -132,16 +132,14 @@
 #'
 ds.make<-function(toAssign=NULL, newobj=NULL, datasources=NULL){
 
-  datasources <- .set_datasources(datasources)
+  datasources <- .resolveDatasources(datasources)
 
   if(is.null(toAssign)){
     stop("Please give the name of object to assign or an expression to evaluate and assign.!\n", call.=FALSE)
   }
   
   # create a name by default if user did not provide a name for the new variable
-  if(is.null(newobj)){
-    newobj <- "make.newobj"
-  }
+  newobj <- .resolveNewobjName(newobj, "make.newobj")
 
   # now do the business
   DSI::datashield.assign(datasources, newobj, as.symbol(toAssign))
diff --git a/R/ds.matrix.R b/R/ds.matrix.R
index 5813ebe09..442fa5154 100644
--- a/R/ds.matrix.R
+++ b/R/ds.matrix.R
@@ -145,7 +145,7 @@
 ds.matrix <- function(mdata = NA, from="clientside.scalar", nrows.scalar=NULL, ncols.scalar=NULL, byrow = FALSE,
                      dimnames = NULL, newobj=NULL, datasources=NULL){
 
-  datasources <- .set_datasources(datasources)
+  datasources <- .resolveDatasources(datasources)
 
   # check if a value has been provided for mdata
   if(is.null(mdata)){
@@ -153,9 +153,7 @@ ds.matrix <- function(mdata = NA, from="clientside.scalar", nrows.scalar=NULL, n
   }
 
   # if no value spcified for output object, then specify a default
-  if(is.null(newobj)){
-    newobj <- "matrix.newobj"
-  }
+  newobj <- .resolveNewobjName(newobj, "matrix.newobj")
 
   #process mdata to make transmittable depending on <from>
   #Check that valid from has been specified
diff --git a/R/ds.matrixDet.R b/R/ds.matrixDet.R
index 97bcbff36..1eb61bd35 100644
--- a/R/ds.matrixDet.R
+++ b/R/ds.matrixDet.R
@@ -81,7 +81,7 @@
 #'
 ds.matrixDet<-function(M1=NULL, newobj=NULL, logarithm=FALSE, datasources=NULL){
 
-  datasources <- .set_datasources(datasources)
+  datasources <- .resolveDatasources(datasources)
 
   # check if user has provided the name of matrix representing M1
   if(is.null(M1)){
@@ -98,9 +98,7 @@ ds.matrixDet<-function(M1=NULL, newobj=NULL, logarithm=FALSE, datasources=NULL){
   }
 
   # if no value specified for output object, then specify a default
-  if(is.null(newobj)){
-    newobj <- "matrixdet.newobj"
-  }
+  newobj <- .resolveNewobjName(newobj, "matrixdet.newobj")
 
   # CALL THE MAIN SERVER SIDE ASSIGN FUNCTION
   calltext <- call("matrixDetDS2", M1, logarithm)
diff --git a/R/ds.matrixDet.report.R b/R/ds.matrixDet.report.R
index e2b8061cc..963a10f7c 100644
--- a/R/ds.matrixDet.report.R
+++ b/R/ds.matrixDet.report.R
@@ -77,7 +77,7 @@
 #'
 ds.matrixDet.report<-function(M1=NULL, logarithm=FALSE, datasources=NULL){
 
-  datasources <- .set_datasources(datasources)
+  datasources <- .resolveDatasources(datasources)
 
   # check if user has provided the name of matrix representing M1
   if(is.null(M1)){
diff --git a/R/ds.matrixDiag.R b/R/ds.matrixDiag.R
index 4e03f1d01..8808ace42 100644
--- a/R/ds.matrixDiag.R
+++ b/R/ds.matrixDiag.R
@@ -175,7 +175,7 @@
 #'
 ds.matrixDiag<-function(x1=NULL, aim=NULL, nrows.scalar=NULL, newobj=NULL, datasources=NULL){
 
-  datasources <- .set_datasources(datasources)
+  datasources <- .resolveDatasources(datasources)
 
   # check if a value has been provided for x1
   if(is.null(x1)){
@@ -183,10 +183,7 @@ ds.matrixDiag<-function(x1=NULL, aim=NULL, nrows.scalar=NULL, newobj=NULL, datas
   }
 
   # if no value spcified for output object, then specify a default
-  if(is.null(newobj))
-  {
-    newobj <- "matrixdiag.newobj"
-  }
+  newobj <- .resolveNewobjName(newobj, "matrixdiag.newobj")
 
   #process x1 to make transmittable depending on aim
   #Check that valid aim has been specified
diff --git a/R/ds.matrixDimnames.R b/R/ds.matrixDimnames.R
index b5db1fee1..8d404de95 100644
--- a/R/ds.matrixDimnames.R
+++ b/R/ds.matrixDimnames.R
@@ -83,7 +83,7 @@
 
 ds.matrixDimnames<-function(M1=NULL, dimnames=NULL, newobj=NULL, datasources=NULL){
 
-  datasources <- .set_datasources(datasources)
+  datasources <- .resolveDatasources(datasources)
 
   # check if user has provided the name of matrix representing M1
   if(is.null(M1)){
@@ -91,9 +91,7 @@ ds.matrixDimnames<-function(M1=NULL, dimnames=NULL, newobj=NULL, datasources=NUL
   }
 
   # if no value specified for output object, then specify a default
-  if(is.null(newobj)){
-    newobj <- "matrixdimnames.newobj"
-  }
+  newobj <- .resolveNewobjName(newobj, "matrixdimnames.newobj")
 
 
 
diff --git a/R/ds.matrixInvert.R b/R/ds.matrixInvert.R
index a8902aac9..3e74c2e11 100644
--- a/R/ds.matrixInvert.R
+++ b/R/ds.matrixInvert.R
@@ -79,7 +79,7 @@
 #'
 ds.matrixInvert<-function(M1=NULL, newobj=NULL, datasources=NULL){
 
-  datasources <- .set_datasources(datasources)
+  datasources <- .resolveDatasources(datasources)
 
   # check if user has provided the name of matrix representing M1
   if(is.null(M1)){
@@ -87,9 +87,7 @@ ds.matrixInvert<-function(M1=NULL, newobj=NULL, datasources=NULL){
   }
 
   # if no value specified for output object, then specify a default
-  if(is.null(newobj)){
-    newobj <- "matrixinvert.newobj"
-  }
+  newobj <- .resolveNewobjName(newobj, "matrixinvert.newobj")
 
 # CALL THE MAIN SERVER SIDE FUNCTION
   calltext <- call("matrixInvertDS", M1)
diff --git a/R/ds.matrixMult.R b/R/ds.matrixMult.R
index bdef9abe2..7a4c7dd53 100644
--- a/R/ds.matrixMult.R
+++ b/R/ds.matrixMult.R
@@ -94,7 +94,7 @@
 #'
 ds.matrixMult<-function(M1=NULL, M2=NULL, newobj=NULL, datasources=NULL){
 
-  datasources <- .set_datasources(datasources)
+  datasources <- .resolveDatasources(datasources)
 
   # check if user has provided the name of matrix representing M1
   if(is.null(M1)){
@@ -111,9 +111,7 @@ ds.matrixMult<-function(M1=NULL, M2=NULL, newobj=NULL, datasources=NULL){
 
 
   # if no value spcified for output object, then specify a default
-  if(is.null(newobj)){
-    newobj <- "matrixmult.newobj"
-  }
+  newobj <- .resolveNewobjName(newobj, "matrixmult.newobj")
 
 # CALL THE MAIN SERVER SIDE FUNCTION
   calltext <- call("matrixMultDS", M1, M2)
diff --git a/R/ds.matrixTranspose.R b/R/ds.matrixTranspose.R
index 9286bb286..1f8d66c23 100644
--- a/R/ds.matrixTranspose.R
+++ b/R/ds.matrixTranspose.R
@@ -82,7 +82,7 @@
 #'
 ds.matrixTranspose<-function(M1=NULL, newobj=NULL, datasources=NULL){
 
-  datasources <- .set_datasources(datasources)
+  datasources <- .resolveDatasources(datasources)
 
   # check if user has provided the name of matrix representing M1
   if(is.null(M1)){
@@ -90,9 +90,7 @@ ds.matrixTranspose<-function(M1=NULL, newobj=NULL, datasources=NULL){
   }
 
   # if no value spcified for output object, then specify a default
-  if(is.null(newobj)){
-    newobj <- "matrixtranspose.newobj"
-  }
+  newobj <- .resolveNewobjName(newobj, "matrixtranspose.newobj")
 
 # CALL THE MAIN SERVER SIDE FUNCTION
   calltext <- call("matrixTransposeDS", M1)
diff --git a/R/ds.mdPattern.R b/R/ds.mdPattern.R
index 0c083e946..8ab9f5978 100644
--- a/R/ds.mdPattern.R
+++ b/R/ds.mdPattern.R
@@ -115,7 +115,7 @@
 #'
 ds.mdPattern <- function(x = NULL, type = 'split', datasources = NULL, classConsistencyCheck = TRUE){
 
-  datasources <- .set_datasources(datasources)
+  datasources <- .resolveDatasources(datasources)
 
   if(is.null(x)){
     stop("Please provide the name of a data frame or matrix!", call.=FALSE)
diff --git a/R/ds.mean.R b/R/ds.mean.R
index accbc2c3f..b69450f5c 100644
--- a/R/ds.mean.R
+++ b/R/ds.mean.R
@@ -97,7 +97,7 @@
 #'
 ds.mean <- function(x=NULL, type='split', save.mean.Nvalid=FALSE, datasources=NULL, classConsistencyCheck=FALSE){
 
-  datasources <- .set_datasources(datasources)
+  datasources <- .resolveDatasources(datasources)
   
   if(is.null(x)){
     stop("Please provide the name of the input object!", call.=FALSE)
diff --git a/R/ds.meanSdGp.R b/R/ds.meanSdGp.R
index 810c5c1b8..e5cce2731 100644
--- a/R/ds.meanSdGp.R
+++ b/R/ds.meanSdGp.R
@@ -103,7 +103,7 @@
 #'
 ds.meanSdGp <- function(x=NULL, y=NULL, type='both', datasources=NULL, classConsistencyCheck=TRUE){
 
-  datasources <- .set_datasources(datasources)
+  datasources <- .resolveDatasources(datasources)
 
   if(is.null(x)){
     stop("Please provide the name of the input vector!", call.=FALSE)
@@ -130,8 +130,8 @@ ds.meanSdGp <- function(x=NULL, y=NULL, type='both', datasources=NULL, classCons
   if(classConsistencyCheck){
     # check the summarised variable (x) and grouping factor (y) each have the
     # same class in all studies
-    .checkClassConsistency(output, field = "class.x", object_name = x)
-    .checkClassConsistency(output, field = "class.index", object_name = y)
+    .checkClassConsistency(output, field = "class.x", objectName = x)
+    .checkClassConsistency(output, field = "class.index", objectName = y)
   }
 
   numsources <- length(output)
diff --git a/R/ds.merge.R b/R/ds.merge.R
index 2eae96207..95695b6ec 100644
--- a/R/ds.merge.R
+++ b/R/ds.merge.R
@@ -114,7 +114,7 @@
 ds.merge <- function(x.name=NULL,y.name=NULL, by.x.names=NULL, by.y.names=NULL,all.x=FALSE,all.y=FALSE,
 			 sort=TRUE, suffixes = c(".x",".y"), no.dups=TRUE, incomparables=NULL, newobj=NULL, datasources=NULL){
 
-  datasources <- .set_datasources(datasources)
+  datasources <- .resolveDatasources(datasources)
 
   # dataframe names
   if(is.null(x.name)){
@@ -147,9 +147,7 @@ ds.merge <- function(x.name=NULL,y.name=NULL, by.x.names=NULL, by.y.names=NULL,a
   suffixes.transmit <- paste(suffixes, collapse=",")
 
   # create a name by default if user did not provide a name for the new dataframe
-  if(is.null(newobj)){
-    newobj <- "merge.newobj"
-  }
+  newobj <- .resolveNewobjName(newobj, "merge.newobj")
 
   # call the server side function
 	calltext <- call("mergeDS", x.name, y.name, by.x.names.transmit, by.y.names.transmit, all.x, all.y,
diff --git a/R/ds.metadata.R b/R/ds.metadata.R
index 2e080f017..c3399bcca 100644
--- a/R/ds.metadata.R
+++ b/R/ds.metadata.R
@@ -50,7 +50,7 @@
 ds.metadata = function(x=NULL, datasources=NULL)
 {
 
-    datasources <- .set_datasources(datasources)
+    datasources <- .resolveDatasources(datasources)
 
     #####################################################################################
     #MODULE 3: SET UP KEY VARIABLES ALLOWING FOR DIFFERENT INPUT FORMATS                #
diff --git a/R/ds.mice.R b/R/ds.mice.R
index 38e271572..6b2ae977f 100644
--- a/R/ds.mice.R
+++ b/R/ds.mice.R
@@ -49,7 +49,7 @@
 ds.mice <- function(data=NULL, m=5, maxit=5, method=NULL, predictorMatrix=NULL, post=NULL, 
                     seed=NA, newobj_mids=NULL, newobj_df=NULL, datasources=NULL){
   
-  datasources <- .set_datasources(datasources)
+  datasources <- .resolveDatasources(datasources)
 
   # verify that 'data' was set
   if(is.null(data)){
diff --git a/R/ds.names.R b/R/ds.names.R
index 1466ce8d3..8849c1e6a 100644
--- a/R/ds.names.R
+++ b/R/ds.names.R
@@ -69,7 +69,7 @@
 #'
 ds.names <- function(xname=NULL, datasources=NULL){
 
-  datasources <- .set_datasources(datasources)
+  datasources <- .resolveDatasources(datasources)
 
   if(is.null(xname)){
     stop("Please provide the name of the input list!", call.=FALSE)
diff --git a/R/ds.ns.R b/R/ds.ns.R
index e1e101ef0..6dd598c63 100644
--- a/R/ds.ns.R
+++ b/R/ds.ns.R
@@ -36,12 +36,10 @@
 ds.ns <- function(x, df = NULL, knots = NULL, intercept = FALSE, Boundary.knots = NULL, 
                   newobj=NULL, datasources=NULL){
   
-  datasources <- .set_datasources(datasources)
+  datasources <- .resolveDatasources(datasources)
   
   # create a name by default if user did not provide a name for the new variable
-  if(is.null(newobj)){
-    newobj <- "ns.newobj"
-  }
+  newobj <- .resolveNewobjName(newobj, "ns.newobj")
   
   # now do the business
   calltext <- call("nsDS", x, df, knots, intercept, Boundary.knots)
diff --git a/R/ds.numNA.R b/R/ds.numNA.R
index b5ad89dce..b94840f32 100644
--- a/R/ds.numNA.R
+++ b/R/ds.numNA.R
@@ -56,7 +56,7 @@
 #'
 ds.numNA <- function(x=NULL, datasources=NULL, classConsistencyCheck=TRUE){
 
-  datasources <- .set_datasources(datasources)
+  datasources <- .resolveDatasources(datasources)
 
   if(is.null(x)){
     stop("Please provide the name of a vector!", call.=FALSE)
diff --git a/R/ds.qlspline.R b/R/ds.qlspline.R
index ca808fb03..e3900a98e 100644
--- a/R/ds.qlspline.R
+++ b/R/ds.qlspline.R
@@ -33,7 +33,7 @@
 #'
 ds.qlspline <- function(x, q, na.rm = TRUE, marginal = FALSE, names = NULL, newobj = NULL, datasources = NULL){
   
-  datasources <- .set_datasources(datasources)
+  datasources <- .resolveDatasources(datasources)
   
   if(is.null(x)){
     stop("Please provide the name of the input variable x!", call.=FALSE)
@@ -44,9 +44,7 @@ ds.qlspline <- function(x, q, na.rm = TRUE, marginal = FALSE, names = NULL, newo
   }
   
   # create a name by default if user did not provide a name for the new variable
-  if(is.null(newobj)){
-    newobj <- "qlspline.newobj"
-  }
+  newobj <- .resolveNewobjName(newobj, "qlspline.newobj")
   
   # now do the business
   calltext <- call("qlsplineDS", x, q, na.rm, marginal, names)
diff --git a/R/ds.quantileMean.R b/R/ds.quantileMean.R
index 4f037f1f7..29dd9373c 100644
--- a/R/ds.quantileMean.R
+++ b/R/ds.quantileMean.R
@@ -69,7 +69,7 @@
 #'
 ds.quantileMean <- function(x=NULL, type='combine', datasources=NULL, classConsistencyCheck=FALSE){
 
-  datasources <- .set_datasources(datasources)
+  datasources <- .resolveDatasources(datasources)
 
   if(is.null(x)){
     stop("Please provide the name of the input vector!", call.=FALSE)
diff --git a/R/ds.rBinom.R b/R/ds.rBinom.R
index 35b8a3ad2..339bbc574 100644
--- a/R/ds.rBinom.R
+++ b/R/ds.rBinom.R
@@ -106,12 +106,10 @@
 #' @export
 ds.rBinom<-function(samp.size=1,size=0,prob=1, newobj=NULL, seed.as.integer=NULL, return.full.seed.as.set=FALSE, datasources=NULL){
 
-  datasources <- .set_datasources(datasources)
+  datasources <- .resolveDatasources(datasources)
 
   # create a name by default if user did not provide a name for the new variable
-  if(is.null(newobj)){
-    newobj <- "rbinom.newobj"
-  }
+  newobj <- .resolveNewobjName(newobj, "rbinom.newobj")
 
 ########################
 #TEST SEED PRIMING VALUE
@@ -154,8 +152,8 @@ return(mess2)
 }
 
 numsources<-length(datasources)
-size<-.expand_to_studies(size, "size", numsources)
-prob<-.expand_to_studies(prob, "prob", numsources)
+size<-.expandToStudies(size, "size", numsources)
+prob<-.expandToStudies(prob, "prob", numsources)
 
 size.valid<-1
 if(is.numeric(size)){
diff --git a/R/ds.rNorm.R b/R/ds.rNorm.R
index d2e035b8b..46a3d7b8f 100644
--- a/R/ds.rNorm.R
+++ b/R/ds.rNorm.R
@@ -120,7 +120,7 @@
 ds.rNorm<-function(samp.size=1,mean=0,sd=1, newobj="newObject", seed.as.integer=NULL, return.full.seed.as.set=FALSE,
                      force.output.to.k.decimal.places=9,datasources=NULL){
 
-  datasources <- .set_datasources(datasources)
+  datasources <- .resolveDatasources(datasources)
 
 ########################
 #TEST SEED PRIMING VALUE
@@ -163,9 +163,9 @@ return(mess2)
 }
 
 numsources<-length(datasources)
-mean<-.expand_to_studies(mean, "mean", numsources)
-sd<-.expand_to_studies(sd, "sd", numsources)
-force.output.to.k.decimal.places<-.expand_to_studies(force.output.to.k.decimal.places, "force.output.to.k.decimal.places", numsources)
+mean<-.expandToStudies(mean, "mean", numsources)
+sd<-.expandToStudies(sd, "sd", numsources)
+force.output.to.k.decimal.places<-.expandToStudies(force.output.to.k.decimal.places, "force.output.to.k.decimal.places", numsources)
 
 sd.valid<-1
 if(is.numeric(sd)){
diff --git a/R/ds.rPois.R b/R/ds.rPois.R
index c4d56448d..4840eaaea 100644
--- a/R/ds.rPois.R
+++ b/R/ds.rPois.R
@@ -102,7 +102,7 @@
 #' @export
 ds.rPois<-function(samp.size=1,lambda=1, newobj="newObject", seed.as.integer=NULL, return.full.seed.as.set=FALSE, datasources=NULL){
 
-  datasources <- .set_datasources(datasources)
+  datasources <- .resolveDatasources(datasources)
 
 ########################
 #TEST SEED PRIMING VALUE
@@ -145,7 +145,7 @@ return(mess2)
 }
 
 numsources<-length(datasources)
-lambda<-.expand_to_studies(lambda, "lambda", numsources)
+lambda<-.expandToStudies(lambda, "lambda", numsources)
 
 lambda.valid<-1
 if(is.numeric(lambda)){
diff --git a/R/ds.rUnif.R b/R/ds.rUnif.R
index e09ed4910..71fe5bec3 100644
--- a/R/ds.rUnif.R
+++ b/R/ds.rUnif.R
@@ -128,7 +128,7 @@
 ds.rUnif<-function(samp.size=1,min=0,max=1, newobj="newObject", seed.as.integer=NULL, return.full.seed.as.set=FALSE,
                      force.output.to.k.decimal.places=9,datasources=NULL){
 
-  datasources <- .set_datasources(datasources)
+  datasources <- .resolveDatasources(datasources)
 
 ########################
 #TEST SEED PRIMING VALUE
@@ -172,9 +172,9 @@ return(mess2)
 }
 
 numsources<-length(datasources)
-min<-.expand_to_studies(min, "min", numsources)
-max<-.expand_to_studies(max, "max", numsources)
-force.output.to.k.decimal.places<-.expand_to_studies(force.output.to.k.decimal.places, "force.output.to.k.decimal.places", numsources)
+min<-.expandToStudies(min, "min", numsources)
+max<-.expandToStudies(max, "max", numsources)
+force.output.to.k.decimal.places<-.expandToStudies(force.output.to.k.decimal.places, "force.output.to.k.decimal.places", numsources)
 
 
 minmax.valid<-1
diff --git a/R/ds.rbind.R b/R/ds.rbind.R
index 995b719e2..90ee2a89f 100644
--- a/R/ds.rbind.R
+++ b/R/ds.rbind.R
@@ -83,7 +83,7 @@
 ds.rbind<-function(x=NULL, DataSHIELD.checks=FALSE, force.colnames=NULL, newobj=NULL,
                    datasources=NULL, notify.of.progress=FALSE, classConsistencyCheck=TRUE){
 
-  datasources <- .set_datasources(datasources)
+  datasources <- .resolveDatasources(datasources)
 
   if(is.null(x)){
     stop("Please provide a vector of character strings holding the name of the input elements!", call.=FALSE)
@@ -104,9 +104,7 @@ ds.rbind<-function(x=NULL, DataSHIELD.checks=FALSE, force.colnames=NULL, newobj=
   }
   
   # check newobj not actively declared as null
-  if(is.null(newobj)){
-    newobj <- "rbind.newobj"
-  }
+  newobj <- .resolveNewobjName(newobj, "rbind.newobj")
 
 #CREATE THE VECTOR OF COLUMN NAMES
 if(!is.null(force.colnames)){
diff --git a/R/ds.reShape.R b/R/ds.reShape.R
index 209734f2f..bf7a2e2fd 100644
--- a/R/ds.reShape.R
+++ b/R/ds.reShape.R
@@ -82,7 +82,7 @@
 ds.reShape <- function(data.name=NULL, varying=NULL, v.names=NULL, timevar.name="time", idvar.name="id",
                             drop=NULL, direction=NULL, sep=".", newobj="newObject", datasources=NULL){
 
-  datasources <- .set_datasources(datasources)
+  datasources <- .resolveDatasources(datasources)
 
   if(is.null(data.name)){
     stop("Please provide the name of the list that holds the input vectors!", call.=FALSE)
diff --git a/R/ds.recodeValues.R b/R/ds.recodeValues.R
index 4038c324e..7dca9b737 100644
--- a/R/ds.recodeValues.R
+++ b/R/ds.recodeValues.R
@@ -79,7 +79,7 @@
 ds.recodeValues <- function(var.name=NULL, values2replace.vector=NULL, new.values.vector=NULL, 
                             missing=NULL, newobj=NULL, datasources=NULL, notify.of.progress=FALSE){
 
-  datasources <- .set_datasources(datasources)
+  datasources <- .resolveDatasources(datasources)
 
   # check user has provided the name of the variable to be recoded
   if(is.null(var.name)){
@@ -120,9 +120,7 @@ ds.recodeValues <- function(var.name=NULL, values2replace.vector=NULL, new.value
     new.values.transmit <- NULL
   }
     
-  if(is.null(newobj)){
-    newobj <- paste0(var.name, "_recoded")
-  }
+  newobj <- .resolveNewobjName(newobj, paste0(var.name, "_recoded"))
 
   calltext <- call("recodeValuesDS", var.name, values2replace.transmit, new.values.transmit, missing)
   DSI::datashield.assign(datasources, newobj, calltext)
diff --git a/R/ds.rep.R b/R/ds.rep.R
index 72c9177a5..53ccaa92e 100644
--- a/R/ds.rep.R
+++ b/R/ds.rep.R
@@ -96,7 +96,7 @@ ds.rep<-function(x1=NULL,  times=NA,  length.out=NA, each=1,
 				source.length.out=NULL,source.each=NULL,
 				x1.includes.characters=FALSE,newobj=NULL,datasources=NULL){
 
-  datasources <- .set_datasources(datasources)
+  datasources <- .resolveDatasources(datasources)
 
   # check if a value has been provided for x1
   if(is.null(x1)){
@@ -104,10 +104,7 @@ ds.rep<-function(x1=NULL,  times=NA,  length.out=NA, each=1,
   }
 
   # if no value specified for output object, then specify a default
-  if(is.null(newobj))
-  {
-    newobj <- paste0("seq.vect")
-  }
+  newobj <- .resolveNewobjName(newobj, paste0("seq.vect"))
 
 #set up aliases for 'clientside', 'serverside' as 'c' and 's'
 if(source.x1=='c')source.x1<-'clientside'
diff --git a/R/ds.replaceNA.R b/R/ds.replaceNA.R
index 1ec2d3a9f..8f41e8984 100644
--- a/R/ds.replaceNA.R
+++ b/R/ds.replaceNA.R
@@ -92,7 +92,7 @@
 #' 
 ds.replaceNA <- function(x=NULL, forNA=NULL, newobj=NULL, datasources=NULL){
 
-  datasources <- .set_datasources(datasources)
+  datasources <- .resolveDatasources(datasources)
 
   if(is.null(x)){
     stop("Please provide the name of a vector!", call.=FALSE)
@@ -119,9 +119,7 @@ ds.replaceNA <- function(x=NULL, forNA=NULL, newobj=NULL, datasources=NULL){
     }
   }
 
-  if(is.null(newobj)){
-    newobj <- "replacena.newobj"
-  }
+  newobj <- .resolveNewobjName(newobj, "replacena.newobj")
 
   # call the server side function and doo the replacement for each server
   for(i in 1:length(datasources)){
diff --git a/R/ds.rm.R b/R/ds.rm.R
index 9e104228a..90b308017 100644
--- a/R/ds.rm.R
+++ b/R/ds.rm.R
@@ -69,7 +69,7 @@
 
 ds.rm<-function(x.names=NULL, datasources=NULL){
     
-    datasources <- .set_datasources(datasources)
+    datasources <- .resolveDatasources(datasources)
     
     if (is.null(x.names)) {
         stop("Please provide the names of the objects to be deleted (eg 'object.name') as the x.names argument", call.=FALSE)
diff --git a/R/ds.rowColCalc.R b/R/ds.rowColCalc.R
index 7aecbba04..6a963650f 100644
--- a/R/ds.rowColCalc.R
+++ b/R/ds.rowColCalc.R
@@ -68,7 +68,7 @@
 #' 
 ds.rowColCalc <- function(x=NULL, operation=NULL, newobj=NULL, datasources=NULL){
 
-  datasources <- .set_datasources(datasources)
+  datasources <- .resolveDatasources(datasources)
 
   if(is.null(x)){
     stop("Please provide the name of a data.frame or matrix!", call.=FALSE)
@@ -89,9 +89,7 @@ ds.rowColCalc <- function(x=NULL, operation=NULL, newobj=NULL, datasources=NULL)
   indx <- which(ops == operation)
 
   # create a name by default if user did not provide a name for the new variable
-  if(is.null(newobj)){
-    newobj <- "rowcolcalc.newobj"
-  }
+  newobj <- .resolveNewobjName(newobj, "rowcolcalc.newobj")
 
   # call the server side function that does the job
   DSI::datashield.assign(datasources, newobj, call("rowColCalcDS", dataset.name=x, operation=indx))
diff --git a/R/ds.sample.R b/R/ds.sample.R
index 9128a9e18..80c92e34f 100644
--- a/R/ds.sample.R
+++ b/R/ds.sample.R
@@ -130,7 +130,7 @@
 ds.sample<-function(x=NULL,  size=NULL, seed.as.integer=NULL, replace=FALSE, prob = NULL, newobj=NULL,datasources=NULL, notify.of.progress=FALSE){
  
 
-  datasources <- .set_datasources(datasources)
+  datasources <- .resolveDatasources(datasources)
 
   # check if a value has been provided for x
   if(is.null(x)){
@@ -145,10 +145,7 @@ ds.sample<-function(x=NULL,  size=NULL, seed.as.integer=NULL, replace=FALSE, pro
   }
 
   # if no value specified for output object, then specify a default
-  if(is.null(newobj))
-  {
-    newobj <- "newobj.sample"
-  }
+  newobj <- .resolveNewobjName(newobj, "newobj.sample")
 
 ########################
 #TEST SEED PRIMING VALUE
diff --git a/R/ds.scatterPlot.R b/R/ds.scatterPlot.R
index 6a76d7986..4ee76e92c 100644
--- a/R/ds.scatterPlot.R
+++ b/R/ds.scatterPlot.R
@@ -139,7 +139,7 @@ ds.scatterPlot <- function(x=NULL, y=NULL, method='deterministic', k=3, noise=0.
     stop("Please provide the name of the y-variable", call.=FALSE)
   }
 
-  datasources <- .set_datasources(datasources)
+  datasources <- .resolveDatasources(datasources)
 
   # Save par and setup reseting of par values
   old_par <- graphics::par(no.readonly = TRUE)
@@ -163,8 +163,8 @@ ds.scatterPlot <- function(x=NULL, y=NULL, method='deterministic', k=3, noise=0.
   # call the server-side function that generates the x and y coordinates of the centroids
   output <- datashield.aggregate(datasources, call("scatterPlotDS", x.name=x, y.name=y, method.indicator=method.indicator, k=k, noise=noise))
   if(classConsistencyCheck){
-    .checkClassConsistency(output, field = "class.x", object_name = x)
-    .checkClassConsistency(output, field = "class.y", object_name = y)
+    .checkClassConsistency(output, field = "class.x", objectName = x)
+    .checkClassConsistency(output, field = "class.y", objectName = y)
   }
 
   pooled.points.x <- c()
diff --git a/R/ds.seq.R b/R/ds.seq.R
index 13fc644a4..ee81f29d4 100644
--- a/R/ds.seq.R
+++ b/R/ds.seq.R
@@ -117,7 +117,7 @@
 ds.seq<-function(FROM.value.char = "1", BY.value.char = "1", TO.value.char=NULL, LENGTH.OUT.value.char = NULL, ALONG.WITH.name=NULL,
                    newobj="newObj", datasources=NULL) {
 ###datasources
-  datasources <- .set_datasources(datasources)
+  datasources <- .resolveDatasources(datasources)
 
 ###FROM.value.char
   # check FROM.value.char is valid
diff --git a/R/ds.setSeed.R b/R/ds.setSeed.R
index 5192f7536..2768c540e 100644
--- a/R/ds.setSeed.R
+++ b/R/ds.setSeed.R
@@ -87,7 +87,7 @@
 #' @export
 ds.setSeed<-function(seed.as.integer=NULL,datasources=NULL){
 
-  datasources <- .set_datasources(datasources)
+  datasources <- .resolveDatasources(datasources)
 
 
 seed.valid<-0
diff --git a/R/ds.skewness.R b/R/ds.skewness.R
index 52f0c87a9..4f4525718 100644
--- a/R/ds.skewness.R
+++ b/R/ds.skewness.R
@@ -81,7 +81,7 @@
 #' 
 ds.skewness <- function(x=NULL, method=1, type='both', datasources=NULL, classConsistencyCheck=FALSE){
 
-  datasources <- .set_datasources(datasources)
+  datasources <- .resolveDatasources(datasources)
 
   if(is.null(x)){
     stop("Please provide the name of the input vector!", call.=FALSE)
diff --git a/R/ds.sqrt.R b/R/ds.sqrt.R
index 76a7538ec..332088f08 100644
--- a/R/ds.sqrt.R
+++ b/R/ds.sqrt.R
@@ -71,15 +71,13 @@
 #'
 ds.sqrt <- function(x=NULL, newobj=NULL, datasources=NULL){
 
-  datasources <- .set_datasources(datasources)
+  datasources <- .resolveDatasources(datasources)
 
   if(is.null(x)){
     stop("Please provide the name of the input object!", call.=FALSE)
   }
 
-  if(is.null(newobj)){
-    newobj <- "sqrt.newobj"
-  }
+  newobj <- .resolveNewobjName(newobj, "sqrt.newobj")
 
   cally <- call("sqrtDS", x)
   DSI::datashield.assign(datasources, newobj, cally)
diff --git a/R/ds.summary.R b/R/ds.summary.R
index bac5cb62b..19876a274 100644
--- a/R/ds.summary.R
+++ b/R/ds.summary.R
@@ -67,7 +67,7 @@
 #'
 ds.summary <- function(x=NULL, datasources=NULL){
 
-  datasources <- .set_datasources(datasources)
+  datasources <- .resolveDatasources(datasources)
 
   if(is.null(x)){
     stop("Please provide the name of the input vector!", call.=FALSE)
diff --git a/R/ds.table.R b/R/ds.table.R
index 328925aaa..951cf186e 100644
--- a/R/ds.table.R
+++ b/R/ds.table.R
@@ -191,7 +191,7 @@ ds.table <- function(rvar=NULL, cvar=NULL, stvar=NULL, report.chisq.tests=FALSE,
 				          	table.assign=FALSE,	newobj=NULL, datasources=NULL, 
 				          	force.nfilter=NULL){
   
-  datasources <- .set_datasources(datasources)
+  datasources <- .resolveDatasources(datasources)
 
   # check if a value has been provided for rvar
   if(is.null(rvar)){
@@ -332,10 +332,7 @@ ds.table <- function(rvar=NULL, cvar=NULL, stvar=NULL, report.chisq.tests=FALSE,
 if(table.assign)
 	{
 
-	if(is.null(newobj))
-		{
-		newobj<-"table.newobj"
-		}
+	newobj <- .resolveNewobjName(newobj, "table.newobj")
 		
 
 # CALL THE MAIN SERVER SIDE ASSIGN FUNCTION
diff --git a/R/ds.tapply.R b/R/ds.tapply.R
index 5342c3323..bd75001f4 100644
--- a/R/ds.tapply.R
+++ b/R/ds.tapply.R
@@ -125,7 +125,7 @@
 ds.tapply <- function(X.name=NULL, INDEX.names=NULL, FUN.name=NULL, datasources=NULL){
 
   ###datasources
-  datasources <- .set_datasources(datasources)
+  datasources <- .resolveDatasources(datasources)
 
   ###X.name
   # check if user has provided the name of the column that holds X.name
diff --git a/R/ds.tapply.assign.R b/R/ds.tapply.assign.R
index 14722a942..b9fa21ffa 100644
--- a/R/ds.tapply.assign.R
+++ b/R/ds.tapply.assign.R
@@ -130,7 +130,7 @@
 ds.tapply.assign <- function(X.name=NULL, INDEX.names=NULL, FUN.name=NULL, newobj=NULL, datasources=NULL){
 
   ###datasources
-  datasources <- .set_datasources(datasources)
+  datasources <- .resolveDatasources(datasources)
 
   ###X.name
   # check if user has provided the name of the column that holds X.name
@@ -166,9 +166,7 @@ ds.tapply.assign <- function(X.name=NULL, INDEX.names=NULL, FUN.name=NULL, newob
   }
 
     # create a name by default if user did not provide a name for the new tapply object
-  if(is.null(newobj)){
-    newobj <- "tapply.assign.newobj"
-  }
+  newobj <- .resolveNewobjName(newobj, "tapply.assign.newobj")
 
   # CALL THE PRIMARY SERVER SIDE FUNCTION
   calltext <- call("tapplyDS.assign", X.name, INDEX.names.transmit, FUN.name)
diff --git a/R/ds.unList.R b/R/ds.unList.R
index 6f98fdddc..c2418cd48 100644
--- a/R/ds.unList.R
+++ b/R/ds.unList.R
@@ -70,7 +70,7 @@
 #' @export
 ds.unList <- function(x.name=NULL, newobj=NULL, datasources=NULL){
 
-  datasources <- .set_datasources(datasources)
+  datasources <- .resolveDatasources(datasources)
 
   if(is.null(x.name)){
     stop("Please provide the name of the input vector!", call.=FALSE)
@@ -78,9 +78,7 @@ ds.unList <- function(x.name=NULL, newobj=NULL, datasources=NULL){
 
 
   # create a name by default if user did not provide a name for the new variable
-  if(is.null(newobj)){
-    newobj <- "unlist.newobj"
-  }
+  newobj <- .resolveNewobjName(newobj, "unlist.newobj")
 
      # call the server side function
   calltext <- call("unListDS", x.name)
diff --git a/R/ds.unique.R b/R/ds.unique.R
index 07ceced2f..97dc824a4 100644
--- a/R/ds.unique.R
+++ b/R/ds.unique.R
@@ -48,15 +48,13 @@
 #'
 ds.unique <- function(x.name = NULL, newobj = NULL, datasources = NULL) {
 
-    datasources <- .set_datasources(datasources)
+    datasources <- .resolveDatasources(datasources)
 
     if (is.null(x.name)) {
         stop("x.name=NULL. Please provide the names of the objects to de-duplicated!", call. = FALSE)
     }
 
-    if (is.null(newobj)) {
-        newobj <- "unique.newobj"
-    }
+    newobj <- .resolveNewobjName(newobj, "unique.newobj")
 
     cally <- call('uniqueDS', x.name)
     DSI::datashield.assign(datasources, newobj, cally)
diff --git a/R/ds.var.R b/R/ds.var.R
index 4247e024b..0256de603 100644
--- a/R/ds.var.R
+++ b/R/ds.var.R
@@ -75,7 +75,7 @@
 #'
 ds.var <- function(x=NULL, type='split', datasources=NULL, classConsistencyCheck=FALSE){
 
-  datasources <- .set_datasources(datasources)
+  datasources <- .resolveDatasources(datasources)
 
   if(is.null(x)){
     stop("Please provide the name of the input object!", call.=FALSE)
diff --git a/R/utils.R b/R/utils.R
index db6ac35d4..63dc43901 100644
--- a/R/utils.R
+++ b/R/utils.R
@@ -6,7 +6,7 @@
 #' @return A list of data sources.
 #' @author Tim Cadman, Genomics Coordination Centre, UMCG, Netherlands
 #' @noRd
-.get_datasources <- function(datasources) {
+.getDatasources <- function(datasources) {
   if (is.null(datasources)) {
     datasources <- datashield.connections_find()
   }
@@ -19,9 +19,9 @@
 #' @importFrom cli cli_abort
 #' @author Tim Cadman, Genomics Coordination Centre, UMCG, Netherlands
 #' @noRd
-.verify_datasources <- function(datasources) {
-  is_connection_class <- sapply(datasources, function(x) inherits(unlist(x), "DSConnection"))
-  if (!all(is_connection_class)) {
+.verifyDatasources <- function(datasources) {
+  isConnectionClass <- vapply(datasources, function(x) inherits(unlist(x), "DSConnection"), logical(1))
+  if (!all(isConnectionClass)) {
     cli_abort("The 'datasources' were expected to be a list of DSConnection-class objects")
   }
 }
@@ -33,9 +33,9 @@
 #' @return A list of verified data sources.
 #' @author Tim Cadman, Genomics Coordination Centre, UMCG, Netherlands
 #' @noRd
-.set_datasources <- function(datasources) {
-  datasources <- .get_datasources(datasources)
-  .verify_datasources(datasources)
+.resolveDatasources <- function(datasources) {
+  datasources <- .getDatasources(datasources)
+  .verifyDatasources(datasources)
   return(datasources)
 }
 
@@ -48,16 +48,16 @@
 #' @param results A named list of server-side aggregate results, one per study,
 #'   each containing the class field named by `field`.
 #' @param field The name of the element holding the class. Default `"class"`.
-#' @param object_name Optional name of the input object, used to make the error
+#' @param objectName Optional name of the input object, used to make the error
 #'   message specific. If `NULL` a generic message is used.
 #' @importFrom cli cli_abort
 #' @return Invisibly returns `NULL`. Called for its side effect (error checking).
 #' @author Tim Cadman, Genomics Coordination Centre, UMCG, Netherlands
 #' @noRd
-.checkClassConsistency <- function(results, field = "class", object_name = NULL) {
+.checkClassConsistency <- function(results, field = "class", objectName = NULL) {
   classes <- lapply(results, function(r) r[[field]])
   if (length(unique(lapply(classes, sort))) > 1) {
-    subject <- if (is.null(object_name)) "The input object" else paste0("'", object_name, "'")
+    subject <- if (is.null(objectName)) "The input object" else paste0("'", objectName, "'")
     cli_abort("{subject} is not of the same class in all studies!")
   }
 }
@@ -73,7 +73,7 @@
 #' @return Invisibly returns `NULL`. Called for its side effect (error checking).
 #' @author Tim Cadman, Genomics Coordination Centre, UMCG, Netherlands
 #' @noRd
-.check_newobj_name <- function(newobj) {
+.checkNewobjName <- function(newobj) {
   if (!is.character(newobj) || length(newobj) != 1) {
     cli_abort("'newobj' must be a single character string")
   }
@@ -91,11 +91,11 @@
 #' @return A validated, single character string.
 #' @author Tim Cadman, Genomics Coordination Centre, UMCG, Netherlands
 #' @noRd
-.set_newobj_name <- function(newobj, default) {
+.resolveNewobjName <- function(newobj, default) {
   if (is.null(newobj)) {
     newobj <- default
   }
-  .check_newobj_name(newobj)
+  .checkNewobjName(newobj)
   return(newobj)
 }
 
@@ -108,7 +108,7 @@
 #' @return Invisibly returns `NULL`. Called for its side effect (error checking).
 #' @author Tim Cadman, Genomics Coordination Centre, UMCG, Netherlands
 #' @noRd
-.check_df_name_provided <- function(df) {
+.checkDfNameProvided <- function(df) {
   if(is.null(df)){
     cli_abort("Please provide the name of a data.frame or matrix!")
   }
@@ -119,19 +119,19 @@
 #' Arguments that may differ between studies can be given either as a single
 #' value, used for every study, or as a vector with one value per study.
 #'
-#' @param values A vector of length 1 or `num_studies`.
-#' @param arg_name The name of the argument, used in the error message.
-#' @param num_studies The number of studies being analysed.
+#' @param values A vector of length 1 or `numStudies`.
+#' @param argName The name of the argument, used in the error message.
+#' @param numStudies The number of studies being analysed.
 #' @importFrom cli cli_abort
-#' @return A vector of length `num_studies`.
+#' @return A vector of length `numStudies`.
 #' @author Tim Cadman, Genomics Coordination Centre, UMCG, Netherlands
 #' @noRd
-.expand_to_studies <- function(values, arg_name, num_studies) {
+.expandToStudies <- function(values, argName, numStudies) {
   if (length(values) == 1) {
-    return(rep(values, num_studies))
+    return(rep(values, numStudies))
   }
-  if (length(values) != num_studies) {
-    cli_abort("'{arg_name}' must be length 1 or one value per study")
+  if (length(values) != numStudies) {
+    cli_abort("'{argName}' must be length 1 or one value per study")
   }
   return(values)
 }
diff --git a/tests/testthat/test-arg-per-study-arguments.R b/tests/testthat/test-arg-per-study-arguments.R
index c8ee48d30..26a79582f 100644
--- a/tests/testthat/test-arg-per-study-arguments.R
+++ b/tests/testthat/test-arg-per-study-arguments.R
@@ -17,7 +17,7 @@ record_server_calls <- function(env = parent.frame()) {
             invisible(NULL)
         },
         datashield.aggregate = function(conns, expr, ...) list(),
-        .set_datasources = function(datasources) datasources,
+        .resolveDatasources = function(datasources) datasources,
         .env = env
     )
     sent
@@ -27,18 +27,18 @@ record_server_calls <- function(env = parent.frame()) {
 # Tests
 #
 
-# context("per-study arguments::arg::.expand_to_studies")
-test_that(".expand_to_studies repeats a single value for every study", {
-    expect_equal(.expand_to_studies(5, "x", 3), c(5, 5, 5))
+# context("per-study arguments::arg::.expandToStudies")
+test_that(".expandToStudies repeats a single value for every study", {
+    expect_equal(.expandToStudies(5, "x", 3), c(5, 5, 5))
 })
 
-test_that(".expand_to_studies keeps one value per study", {
-    expect_equal(.expand_to_studies(c(1, 2, 3), "x", 3), c(1, 2, 3))
+test_that(".expandToStudies keeps one value per study", {
+    expect_equal(.expandToStudies(c(1, 2, 3), "x", 3), c(1, 2, 3))
 })
 
-test_that(".expand_to_studies rejects any other length", {
-    expect_error(.expand_to_studies(c(1, 2), "x", 3), "'x' must be length 1 or one value per\\s+study")
-    expect_error(.expand_to_studies(c(1, 2, 3, 4), "x", 3), "'x' must be length 1 or one value per\\s+study")
+test_that(".expandToStudies rejects any other length", {
+    expect_error(.expandToStudies(c(1, 2), "x", 3), "'x' must be length 1 or one value per\\s+study")
+    expect_error(.expandToStudies(c(1, 2, 3, 4), "x", 3), "'x' must be length 1 or one value per\\s+study")
 })
 
 # context("per-study arguments::arg::ds.rBinom")
diff --git a/tests/testthat/test-utils.R b/tests/testthat/test-utils.R
new file mode 100644
index 000000000..ba0904104
--- /dev/null
+++ b/tests/testthat/test-utils.R
@@ -0,0 +1,14 @@
+#
+# Tests
+#
+
+# context("utils::.resolveNewobjName")
+test_that(".resolveNewobjName applies the default before validating", {
+    expect_equal(.resolveNewobjName(NULL, "x.newobj"), "x.newobj")
+    expect_equal(.resolveNewobjName("my.obj", "x.newobj"), "my.obj")
+})
+
+test_that(".resolveNewobjName rejects anything but a single character string", {
+    expect_error(.resolveNewobjName(23, "x.newobj"), "'newobj' must be a single character string")
+    expect_error(.resolveNewobjName(c("a", "b"), "x.newobj"), "'newobj' must be a single character string")
+})

From b3ec2165ebcf11f9a33c6663eb3566d15b5f8a60 Mon Sep 17 00:00:00 2001
From: Tim Cadman <41470917+timcadman@users.noreply.github.com>
Date: Mon, 2 Nov 2026 15:11:27 +0100
Subject: [PATCH 2/2] Share argument checks in helpers and raise returned
 errors

---
 NAMESPACE                                     |   3 +
 R/ds.Boole.R                                  |  14 +-
 R/ds.abs.R                                    |   4 +-
 R/ds.asCharacter.R                            |   4 +-
 R/ds.asDataMatrix.R                           |   4 +-
 R/ds.asFactor.R                               |   4 +-
 R/ds.asFactorSimple.R                         |   4 +-
 R/ds.asInteger.R                              |   4 +-
 R/ds.asList.R                                 |   4 +-
 R/ds.asLogical.R                              |   4 +-
 R/ds.asMatrix.R                               |   4 +-
 R/ds.asNumeric.R                              |   4 +-
 R/ds.assign.R                                 |   4 +-
 R/ds.auc.R                                    |   8 +-
 R/ds.boxPlot.R                                |   2 +-
 R/ds.boxPlotGG.R                              |   2 +-
 R/ds.bp_standards.R                           |  16 +-
 R/ds.c.R                                      |   4 +-
 R/ds.cbind.R                                  |  47 +----
 R/ds.changeRefGroup.R                         |   8 +-
 R/ds.class.R                                  |   4 +-
 R/ds.colnames.R                               |   2 +-
 R/ds.completeCases.R                          |   4 +-
 R/ds.contourPlot.R                            |  18 +-
 R/ds.cor.R                                    |   6 +-
 R/ds.corTest.R                                |  12 +-
 R/ds.cov.R                                    |   6 +-
 R/ds.dataFrame.R                              |  47 +----
 R/ds.dataFrameSubset.R                        |   4 +-
 R/ds.densityGrid.R                            |  10 +-
 R/ds.dim.R                                    |   6 +-
 R/ds.dmtC2S.R                                 |   7 +-
 R/ds.elspline.R                               |   8 +-
 R/ds.exists.R                                 |   4 +-
 R/ds.exp.R                                    |   4 +-
 R/ds.gamlss.R                                 |   6 +-
 R/ds.getWGSR.R                                |  14 +-
 R/ds.glm.R                                    |  84 ++-------
 R/ds.glmPredict.R                             |   8 +-
 R/ds.glmSLMA.R                                |  46 ++---
 R/ds.glmerSLMA.R                              |  21 +--
 R/ds.heatmapPlot.R                            |  18 +-
 R/ds.hetcor.R                                 |   4 +-
 R/ds.histogram.R                              |  10 +-
 R/ds.igb_standards.R                          |  16 +-
 R/ds.isNA.R                                   |   4 +-
 R/ds.isValid.R                                |   4 +-
 R/ds.kurtosis.R                               |   6 +-
 R/ds.length.R                                 |   8 +-
 R/ds.levels.R                                 |   4 +-
 R/ds.lexis.R                                  |  12 +-
 R/ds.list.R                                   |   4 +-
 R/ds.lmerSLMA.R                               |  20 +--
 R/ds.log.R                                    |   4 +-
 R/ds.ls.R                                     |   5 +-
 R/ds.lspline.R                                |   8 +-
 R/ds.make.R                                   |   4 +-
 R/ds.matrix.R                                 |   8 +-
 R/ds.matrixDet.R                              |   4 +-
 R/ds.matrixDet.report.R                       |   4 +-
 R/ds.matrixDiag.R                             |   9 +-
 R/ds.matrixDimnames.R                         |   4 +-
 R/ds.matrixInvert.R                           |   4 +-
 R/ds.matrixMult.R                             |   8 +-
 R/ds.matrixTranspose.R                        |   4 +-
 R/ds.mdPattern.R                              |   6 +-
 R/ds.mean.R                                   |   6 +-
 R/ds.meanSdGp.R                               |  11 +-
 R/ds.merge.R                                  |  20 +--
 R/ds.metadata.R                               |   4 +-
 R/ds.mice.R                                   |   4 +-
 R/ds.names.R                                  |   4 +-
 R/ds.numNA.R                                  |   4 +-
 R/ds.qlspline.R                               |   8 +-
 R/ds.quantileMean.R                           |   8 +-
 R/ds.rBinom.R                                 |  34 +---
 R/ds.rNorm.R                                  |  34 +---
 R/ds.rPois.R                                  |  31 +---
 R/ds.rUnif.R                                  |  35 +---
 R/ds.rbind.R                                  |  11 +-
 R/ds.reShape.R                                |   4 +-
 R/ds.recodeValues.R                           |   4 +-
 R/ds.rep.R                                    |  20 +--
 R/ds.replaceNA.R                              |  13 +-
 R/ds.rm.R                                     |   4 +-
 R/ds.rowColCalc.R                             |   6 +-
 R/ds.sample.R                                 |  23 +--
 R/ds.scatterPlot.R                            |  10 +-
 R/ds.seq.R                                    |  12 +-
 R/ds.setSeed.R                                |  18 +-
 R/ds.skewness.R                               |   6 +-
 R/ds.sqrt.R                                   |   4 +-
 R/ds.summary.R                                |   4 +-
 R/ds.table.R                                  |  37 ++--
 R/ds.tapply.R                                 |  13 +-
 R/ds.tapply.assign.R                          |  13 +-
 R/ds.unList.R                                 |   4 +-
 R/ds.unique.R                                 |   4 +-
 R/ds.var.R                                    |   4 +-
 R/utils.R                                     | 165 +++++++++++++++---
 tests/testthat/test-_-utils.R                 |  64 +++++++
 tests/testthat/test-arg-ds.Boole.R            |   8 +-
 tests/testthat/test-arg-ds.abs.R              |   2 +-
 tests/testthat/test-arg-ds.asCharacter.R      |   2 +-
 tests/testthat/test-arg-ds.asDataMatrix.R     |   2 +-
 tests/testthat/test-arg-ds.asFactor.R         |   2 +-
 tests/testthat/test-arg-ds.asInteger.R        |   2 +-
 tests/testthat/test-arg-ds.asList.R           |   2 +-
 tests/testthat/test-arg-ds.asLogical.R        |   2 +-
 tests/testthat/test-arg-ds.asMatrix.R         |   2 +-
 tests/testthat/test-arg-ds.asNumeric.R        |   2 +-
 tests/testthat/test-arg-ds.assign.R           |   2 +-
 tests/testthat/test-arg-ds.auc.R              |   4 +-
 tests/testthat/test-arg-ds.c.R                |   2 +-
 tests/testthat/test-arg-ds.cbind.R            |   4 +-
 tests/testthat/test-arg-ds.changeRefGroup.R   |   4 +-
 tests/testthat/test-arg-ds.class.R            |   2 +-
 tests/testthat/test-arg-ds.completeCases.R    |   3 +-
 tests/testthat/test-arg-ds.cor.R              |   4 +-
 tests/testthat/test-arg-ds.corTest.R          |   4 +-
 tests/testthat/test-arg-ds.cov.R              |   4 +-
 tests/testthat/test-arg-ds.dataFrame.R        |   4 +-
 tests/testthat/test-arg-ds.dataFrameSubset.R  |   2 +-
 tests/testthat/test-arg-ds.dim.R              |   4 +-
 tests/testthat/test-arg-ds.exists.R           |   2 +-
 tests/testthat/test-arg-ds.exp.R              |   2 +-
 tests/testthat/test-arg-ds.gamlss.R           |   4 +-
 tests/testthat/test-arg-ds.glm.R              |   4 +-
 tests/testthat/test-arg-ds.glmPredict.R       |   6 +-
 tests/testthat/test-arg-ds.glmSLMA.R          |   2 +-
 tests/testthat/test-arg-ds.glmerSLMA.R        |   7 +-
 tests/testthat/test-arg-ds.isNA.R             |   2 +-
 tests/testthat/test-arg-ds.isValid.R          |   2 +-
 tests/testthat/test-arg-ds.kurtosis.R         |   8 +-
 tests/testthat/test-arg-ds.length.R           |   4 +-
 tests/testthat/test-arg-ds.levels.R           |   2 +-
 tests/testthat/test-arg-ds.lexis.R            |   2 +-
 tests/testthat/test-arg-ds.list.R             |   2 +-
 tests/testthat/test-arg-ds.lmerSLMA.R         |   7 +-
 tests/testthat/test-arg-ds.log.R              |   2 +-
 tests/testthat/test-arg-ds.ls.R               |  15 +-
 tests/testthat/test-arg-ds.make.R             |   2 +-
 tests/testthat/test-arg-ds.matrix.R           |   3 +-
 tests/testthat/test-arg-ds.matrixDet.R        |   3 +-
 tests/testthat/test-arg-ds.matrixDet.report.R |   3 +-
 tests/testthat/test-arg-ds.matrixDiag.R       |   4 +-
 tests/testthat/test-arg-ds.matrixDimnames.R   |   3 +-
 tests/testthat/test-arg-ds.matrixInvert.R     |   3 +-
 tests/testthat/test-arg-ds.matrixMult.R       |   3 +-
 tests/testthat/test-arg-ds.matrixTranspose.R  |   3 +-
 tests/testthat/test-arg-ds.mean.R             |   4 +-
 tests/testthat/test-arg-ds.meanSdGp.R         |   2 +-
 tests/testthat/test-arg-ds.merge.R            |   8 +-
 tests/testthat/test-arg-ds.mice.R             |   2 +-
 tests/testthat/test-arg-ds.names.R            |   2 +-
 tests/testthat/test-arg-ds.ns.R               |   2 +-
 tests/testthat/test-arg-ds.numNA.R            |   2 +-
 tests/testthat/test-arg-ds.qlspline.R         |   4 +-
 tests/testthat/test-arg-ds.quantileMean.R     |   4 +-
 tests/testthat/test-arg-ds.rBinom.R           |   5 +-
 tests/testthat/test-arg-ds.rNorm.R            |   5 +-
 tests/testthat/test-arg-ds.rPois.R            |   5 +-
 tests/testthat/test-arg-ds.rUnif.R            |   5 +-
 tests/testthat/test-arg-ds.rbind.R            |   2 +-
 tests/testthat/test-arg-ds.reShape.R          |   8 +-
 tests/testthat/test-arg-ds.recodeValues.R     |   2 +-
 tests/testthat/test-arg-ds.rep.R              |   3 +-
 tests/testthat/test-arg-ds.replaceNA.R        |   4 +-
 tests/testthat/test-arg-ds.rm.R               |   2 +-
 tests/testthat/test-arg-ds.rowColCalc.R       |   4 +-
 tests/testthat/test-arg-ds.sample.R           |   9 +-
 tests/testthat/test-arg-ds.setSeed.R          |   3 +-
 tests/testthat/test-arg-ds.skewness.R         |   8 +-
 tests/testthat/test-arg-ds.sqrt.R             |   2 +-
 tests/testthat/test-arg-ds.summary.R          |   2 +-
 tests/testthat/test-arg-ds.table.R            |  13 +-
 tests/testthat/test-arg-ds.tapply.R           |  14 +-
 tests/testthat/test-arg-ds.tapply.assign.R    |  14 +-
 tests/testthat/test-arg-ds.unList.R           |   2 +-
 tests/testthat/test-arg-ds.unique.R           |   4 +-
 tests/testthat/test-arg-ds.var.R              |   2 +-
 tests/testthat/test-arg-per-study-arguments.R |  34 ++--
 tests/testthat/test-disc-ds.table.R           |  11 +-
 tests/testthat/test-smk-ds.lmerSLMA.R         |   3 +-
 tests/testthat/test-smk-ds.mdPattern.R        |   2 +-
 tests/testthat/test-smk-ds.rBinom.R           |   2 +-
 tests/testthat/test-smk-ds.rNorm.R            |   2 +-
 tests/testthat/test-smk-ds.rPois.R            |   2 +-
 tests/testthat/test-smk-ds.rUnif.R            |   2 +-
 tests/testthat/test-utils.R                   |  14 --
 190 files changed, 604 insertions(+), 1082 deletions(-)
 create mode 100644 tests/testthat/test-_-utils.R
 delete mode 100644 tests/testthat/test-utils.R

diff --git a/NAMESPACE b/NAMESPACE
index 88498755c..646eb7478 100644
--- a/NAMESPACE
+++ b/NAMESPACE
@@ -121,6 +121,9 @@ import(DSI)
 import(data.table)
 importFrom(DSI,datashield.connections_find)
 importFrom(cli,cli_abort)
+importFrom(cli,cli_inform)
+importFrom(cli,cli_verbatim)
+importFrom(cli,cli_warn)
 importFrom(stats,
   as.formula,
   na.omit,
diff --git a/R/ds.Boole.R b/R/ds.Boole.R
index ae4e81b10..743263532 100644
--- a/R/ds.Boole.R
+++ b/R/ds.Boole.R
@@ -107,23 +107,17 @@ ds.Boole<-function(V1=NULL, V2=NULL, Boolean.operator=NULL, numeric.output=TRUE,
   datasources <- .resolveDatasources(datasources)
 
   # check if user has provided the name of the column or scalar that holds V1
-  if(is.null(V1)){
-    stop("Please provide the name of the column or scalar that holds V1!", call.=FALSE)
-  }
+  .checkArgProvided(V1, "the name of the column or scalar that holds V1")
 
   # check if user has provided the name of a column or scalar holding V2 or has declared a scalar value: eg '3'
-  if(is.null(V2)){
-    stop("Please provide the name of a column or scalar holding V2 or declare a scalar in character format: eg '3'", call.=FALSE)
-  }
+  .checkArgProvided(V2, "the name of a column or scalar that holds V2")
 
   # check if user has provided a Boolean operator in character format: eg '==' or '>=' or '<' or '!='
-  if(is.null(Boolean.operator)){
-    stop("Please provide a Boolean operator in character format: eg '==' or '>=' or '<' or '!='", call.=FALSE)
-  }
+  .checkArgProvided(Boolean.operator, "a Boolean operator in character format, such as '==' or '>='")
 
   #check if na.assign has legal value
   if(!(na.assign=="NA"||na.assign=="0"||na.assign=="1")){
-    stop("Error: na.assign must be a character string taking value 'NA', '0' or '1'- if <na.action> not specified default is 'NA'", call.=FALSE)
+    .abortInvalidChoice("na.assign", c("NA", "0", "1"))
   }
 
   # create a name by default if user did not provide a name for the new variable
diff --git a/R/ds.abs.R b/R/ds.abs.R
index b434e30c1..d07d82dd2 100644
--- a/R/ds.abs.R
+++ b/R/ds.abs.R
@@ -75,9 +75,7 @@ ds.abs <- function(x=NULL, newobj=NULL, datasources=NULL){
 
   datasources <- .resolveDatasources(datasources)
 
-  if(is.null(x)){
-    stop("Please provide the name of the input object!", call.=FALSE)
-  }
+  .checkArgProvided(x, "the name of the input object")
 
   newobj <- .resolveNewobjName(newobj, "abs.newobj")
 
diff --git a/R/ds.asCharacter.R b/R/ds.asCharacter.R
index f2b359ecf..63df864af 100644
--- a/R/ds.asCharacter.R
+++ b/R/ds.asCharacter.R
@@ -58,9 +58,7 @@ ds.asCharacter <- function(x.name=NULL, newobj=NULL, datasources=NULL){
 
   datasources <- .resolveDatasources(datasources)
 
-  if(is.null(x.name)){
-    stop("Please provide the name of the input vector!", call.=FALSE)
-  }
+  .checkArgProvided(x.name, "the name of the input vector")
   
   newobj <- .resolveNewobjName(newobj, "ascharacter.newobj")
 
diff --git a/R/ds.asDataMatrix.R b/R/ds.asDataMatrix.R
index 140d55bc2..a7d322ffb 100644
--- a/R/ds.asDataMatrix.R
+++ b/R/ds.asDataMatrix.R
@@ -57,9 +57,7 @@ ds.asDataMatrix <- function(x.name=NULL, newobj=NULL, datasources=NULL){
 
   datasources <- .resolveDatasources(datasources)
 
-  if(is.null(x.name)){
-    stop("Please provide the name of the input vector!", call.=FALSE)
-  }
+  .checkArgProvided(x.name, "the name of the input vector")
   
   newobj <- .resolveNewobjName(newobj, "asdatamatrix.newobj")
 
diff --git a/R/ds.asFactor.R b/R/ds.asFactor.R
index cbed01eec..023eb49cf 100644
--- a/R/ds.asFactor.R
+++ b/R/ds.asFactor.R
@@ -191,9 +191,7 @@ ds.asFactor <- function(input.var.name=NULL, newobj.name=NULL, forced.factor.lev
   datasources <- .resolveDatasources(datasources)
 
   # check if user has provided the name of the column that holds the input variable
-  if(is.null(input.var.name)){
-    stop("Please provide the name of the variable that is to be converted to a factor e.g. 'varname'", call.=FALSE)
-  }
+  .checkArgProvided(input.var.name, "the name of the variable to convert to a factor")
 
   # check if user has provided the name of the input variable in a correct character format
   if(!is.character(input.var.name)){
diff --git a/R/ds.asFactorSimple.R b/R/ds.asFactorSimple.R
index 6ca510d42..aecc10265 100644
--- a/R/ds.asFactorSimple.R
+++ b/R/ds.asFactorSimple.R
@@ -27,9 +27,7 @@ ds.asFactorSimple <- function(input.var.name=NULL, newobj.name=NULL, datasources
   datasources <- .resolveDatasources(datasources)
 
   # check if user has provided the name of the column that holds the input variable
-  if(is.null(input.var.name)){
-    stop("Please provide the name of the variable that is to be converted to a factor e.g. 'varname'", call.=FALSE)
-  }
+  .checkArgProvided(input.var.name, "the name of the variable to convert to a factor")
 
   # check if user has provided the name of the input variable in a correct character format
   if(!is.character(input.var.name)){
diff --git a/R/ds.asInteger.R b/R/ds.asInteger.R
index 8c5034519..b34fe567b 100644
--- a/R/ds.asInteger.R
+++ b/R/ds.asInteger.R
@@ -71,9 +71,7 @@ ds.asInteger <- function(x.name=NULL, newobj=NULL, datasources=NULL){
   
   datasources <- .resolveDatasources(datasources)
 
-  if(is.null(x.name)){
-    stop("Please provide the name of the input vector!", call.=FALSE)
-  }
+  .checkArgProvided(x.name, "the name of the input vector")
   
   newobj <- .resolveNewobjName(newobj, "asinteger.newobj")
 
diff --git a/R/ds.asList.R b/R/ds.asList.R
index 29e1897a1..88a4ea2d5 100644
--- a/R/ds.asList.R
+++ b/R/ds.asList.R
@@ -59,9 +59,7 @@ ds.asList <- function(x.name=NULL, newobj=NULL, datasources=NULL){
 
   datasources <- .resolveDatasources(datasources)
 
-  if(is.null(x.name)){
-    stop("Please provide the name of the input vector!", call.=FALSE)
-  }
+  .checkArgProvided(x.name, "the name of the input vector")
 
   newobj <- .resolveNewobjName(newobj, "aslist.newobj")
 
diff --git a/R/ds.asLogical.R b/R/ds.asLogical.R
index e8c59f6e6..cb8f66525 100644
--- a/R/ds.asLogical.R
+++ b/R/ds.asLogical.R
@@ -58,9 +58,7 @@ ds.asLogical <- function(x.name=NULL, newobj=NULL, datasources=NULL){
 
   datasources <- .resolveDatasources(datasources)
 
-  if(is.null(x.name)){
-    stop("Please provide the name of the input vector!", call.=FALSE)
-  }
+  .checkArgProvided(x.name, "the name of the input vector")
   
   newobj <- .resolveNewobjName(newobj, "aslogical.newobj")
 
diff --git a/R/ds.asMatrix.R b/R/ds.asMatrix.R
index 8fbcb17fa..67cf1d48a 100644
--- a/R/ds.asMatrix.R
+++ b/R/ds.asMatrix.R
@@ -60,9 +60,7 @@ ds.asMatrix <- function(x.name=NULL, newobj=NULL, datasources=NULL){
 
   datasources <- .resolveDatasources(datasources)
 
-  if(is.null(x.name)){
-    stop("Please provide the name of the input vector!", call.=FALSE)
-  }
+  .checkArgProvided(x.name, "the name of the input vector")
   
   newobj <- .resolveNewobjName(newobj, "asmatrix.newobj")
 
diff --git a/R/ds.asNumeric.R b/R/ds.asNumeric.R
index 656caa813..7fadcfb55 100644
--- a/R/ds.asNumeric.R
+++ b/R/ds.asNumeric.R
@@ -72,9 +72,7 @@ ds.asNumeric <- function(x.name=NULL, newobj=NULL, datasources=NULL){
 
   datasources <- .resolveDatasources(datasources)
 
-  if(is.null(x.name)){
-    stop("Please provide the name of the input vector!", call.=FALSE)
-  }
+  .checkArgProvided(x.name, "the name of the input vector")
   
   newobj <- .resolveNewobjName(newobj, "asnumeric.newobj")
 
diff --git a/R/ds.assign.R b/R/ds.assign.R
index 836761177..473a614fd 100644
--- a/R/ds.assign.R
+++ b/R/ds.assign.R
@@ -59,9 +59,7 @@ ds.assign <- function(toAssign=NULL, newobj=NULL, datasources=NULL){
   
   datasources <- .resolveDatasources(datasources)
 
-  if(is.null(toAssign)){
-    stop("Please give the name of object to assign or an expression to evaluate and assign.!\n", call.=FALSE)
-  }
+  .checkArgProvided(toAssign, "the name of the object to assign or an expression to evaluate")
 
   # create a name by default if user did not provide a name for the new variable
   newobj <- .resolveNewobjName(newobj, "assign.newobj")
diff --git a/R/ds.auc.R b/R/ds.auc.R
index e1c781480..fd4985d6b 100644
--- a/R/ds.auc.R
+++ b/R/ds.auc.R
@@ -19,14 +19,10 @@ ds.auc <- function(pred=NULL, y=NULL, datasources=NULL){
   datasources <- .resolveDatasources(datasources)
   
   # verify that 'pred' was set
-  if(is.null(pred)){
-    stop("Please provide the name of the vector with predicted values", call.=FALSE)
-  }
+  .checkArgProvided(pred, "the name of the vector of predicted values")
   
   # verify that 'y' was set
-  if(is.null(y)){
-    stop("Please provide the name of the outcome variable", call.=FALSE)
-  }
+  .checkArgProvided(y, "the name of the outcome variable")
   
   cally <- call('aucDS', pred, y)
   output <- DSI::datashield.aggregate(datasources, cally)
diff --git a/R/ds.boxPlot.R b/R/ds.boxPlot.R
index c793e31fd..5a1da5bd8 100644
--- a/R/ds.boxPlot.R
+++ b/R/ds.boxPlot.R
@@ -91,7 +91,7 @@ ds.boxPlot <- function(x, variables = NULL, group = NULL, group2 = NULL, xlabel
 
   # Ensure type is 'pooled' or 'split'
   if((length(type) == 1) && (! any(type %in% c("pooled", "split")))){
-    stop("[type] can only be set to 'pooled' or 'split'")
+    .abortInvalidChoice("type", c("pooled", "split"))
   }
 
   # Determine class of x for dispatch
diff --git a/R/ds.boxPlotGG.R b/R/ds.boxPlotGG.R
index 590296fc3..25f1d912e 100644
--- a/R/ds.boxPlotGG.R
+++ b/R/ds.boxPlotGG.R
@@ -132,7 +132,7 @@ ds.boxPlotGG <- function(x, group = NULL, group2 = NULL, xlabel = "x axis", ylab
     plt <- do.call(gridExtra::grid.arrange, plt)
     
   }
-  else{stop("Invalid type")}
+  else{.abortInvalidChoice("type", c("pooled", "split"))}
   
   return(plt)
   
diff --git a/R/ds.bp_standards.R b/R/ds.bp_standards.R
index f01c1d981..efeb8bad7 100644
--- a/R/ds.bp_standards.R
+++ b/R/ds.bp_standards.R
@@ -35,24 +35,16 @@ ds.bp_standards <- function(sex=NULL, age=NULL, height=NULL, bp=NULL, systolic=T
   datasources <- .resolveDatasources(datasources)
   
   # verify that 'sex' was set
-  if(is.null(sex)){
-    stop("Please provide the name of the sex variable", call.=FALSE)
-  }
+  .checkArgProvided(sex, "the name of the sex variable")
   
   # verify that 'age' was set
-  if(is.null(age)){
-    stop("Please provide the name of the age in months variable", call.=FALSE)
-  }
+  .checkArgProvided(age, "the name of the age in months variable")
   
   # verify that 'height' was set
-  if(is.null(height)){
-    stop("Please provide the name of the height in cm variable", call.=FALSE)
-  }
+  .checkArgProvided(height, "the name of the height in cm variable")
   
   # verify that 'bp' was set
-  if(is.null(bp)){
-    stop("Please provide the name of the blood pressure variable", call.=FALSE)
-  }
+  .checkArgProvided(bp, "the name of the blood pressure variable")
   
   # if no output object specified then provide a default name
   newobj <- .resolveNewobjName(newobj, "bp.newobj")
diff --git a/R/ds.c.R b/R/ds.c.R
index a6a21238d..519aec82b 100644
--- a/R/ds.c.R
+++ b/R/ds.c.R
@@ -62,9 +62,7 @@ ds.c <- function(x=NULL, newobj=NULL, datasources=NULL, classConsistencyCheck=TR
 
   datasources <- .resolveDatasources(datasources)
 
-  if(is.null(x)){
-    stop("x=NULL. Please provide the names of the objects to concatenate!", call.=FALSE)
-  }
+  .checkArgProvided(x, "the names of the objects to concatenate")
 
   # create a name by default if user did not provide a name for the new variable
   newobj <- .resolveNewobjName(newobj, "c.newobj")
diff --git a/R/ds.cbind.R b/R/ds.cbind.R
index 2291eb507..5209b37b7 100644
--- a/R/ds.cbind.R
+++ b/R/ds.cbind.R
@@ -119,57 +119,16 @@ ds.cbind <- function(x=NULL, DataSHIELD.checks=FALSE, force.colnames=NULL, newob
 
   datasources <- .resolveDatasources(datasources)
 
-  if(is.null(x)){
-    stop("Please provide a vector of character strings holding the name of the input elements!", call.=FALSE)
-  }
+  .checkArgProvided(x, "a vector of the names of the input elements")
   
   if(DataSHIELD.checks){
 
     # call the internal function that checks the input object(s) is(are) of the same legal class in all studies.
     if(classConsistencyCheck){
-    for(i in 1:length(x)){
-      typ <- checkClass(datasources, x[i])
-      if(!('data.frame' %in% typ) & !('matrix' %in% typ) & !('factor' %in% typ) & !('character' %in% typ) & !('numeric' %in% typ) & !('integer' %in% typ) & !('logical' %in% typ)){
-        stop("Only objects of type 'data.frame', 'matrix', 'numeric', 'integer', 'character', 'factor' and 'logical' are allowed.", call.=FALSE)
-      }
-    }
+    .checkObjectClasses(datasources, x)
     }
 
-    # check that there are no duplicated column names in the input components
-    for(j in 1:length(datasources)){
-      colNames <- list()
-      for(i in 1:length(x)){
-        typ <- checkClass(datasources, x[i])
-        if(any(typ %in% c('data.frame', 'matrix'))){
-          colNames[[i]] <- ds.colnames(x=x[i], datasources=datasources[j])
-        }
-        if(any(typ %in% c('factor', 'character', 'numeric', 'integer', 'logical'))){
-          colNames[[i]] <- as.character(x[i])
-        }
-        colNames <- unlist(colNames)
-        if(anyDuplicated(colNames) != 0){
-          message("\n Warning: Some column names in study", j, "are duplicated and a suffix '.k' will be added to the kth replicate \n")
-        }
-      }
-    }
-
-    # check that the number of rows is the same in all componets to be cbind
-    for(j in 1:length(datasources)){
-      nrows <- list()
-      for(i in 1:length(x)){
-        typ <- checkClass(datasources, x[i])
-        if(any(typ %in% c('data.frame', 'matrix'))){
-          nrows[[i]] <- ds.dim(x=x[i], type='split', datasources=datasources[j])[[1]][1]
-        }
-        if(any(typ %in% c('factor', 'character', 'numeric', 'integer', 'logical'))){
-          nrows[[i]] <- ds.length(x[i], type='split', datasources=datasources[j])[[1]]
-        }
-      }
-      nrows <- unlist(nrows)
-      if(any(nrows != nrows[1])){
-        stop("The number of rows is not the same in all of the components to be cbind", call.=FALSE)
-      }
-    }
+    .checkMultiObjectConsistency(datasources, x)
 
   }
   
diff --git a/R/ds.changeRefGroup.R b/R/ds.changeRefGroup.R
index 1f1435e27..1ac677b1e 100644
--- a/R/ds.changeRefGroup.R
+++ b/R/ds.changeRefGroup.R
@@ -114,13 +114,9 @@ ds.changeRefGroup <- function(x=NULL, ref=NULL, newobj=NULL, reorderByRef=FALSE,
 
   datasources <- .resolveDatasources(datasources)
 
-  if(is.null(x)){
-    stop("Please provide the name of a vector of type factor!", call.=FALSE)
-  }
+  .checkArgProvided(x, "the name of a factor")
 
-  if(is.null(ref)){
-    stop(" You must indicate a reference level - set the parameter 'ref'.", call.=FALSE)
-  }
+  .checkArgProvided(ref, "a reference level")
   
   # create a name by default if user did not provide a name for the new variable
   newobj <- .resolveNewobjName(newobj, "changerefgroup.newobj")
diff --git a/R/ds.class.R b/R/ds.class.R
index 8d98f02b7..d6474cb98 100644
--- a/R/ds.class.R
+++ b/R/ds.class.R
@@ -57,9 +57,7 @@ ds.class <- function(x=NULL, datasources=NULL) {
 
   datasources <- .resolveDatasources(datasources)
 
-  if(is.null(x)){
-    stop("Please provide the name of the input object!", call.=FALSE)
-  }
+  .checkArgProvided(x, "the name of the input object")
 
   cally <- call('classDS', x)
   output <- DSI::datashield.aggregate(datasources, cally)
diff --git a/R/ds.colnames.R b/R/ds.colnames.R
index 835c3a529..d13cbd9b5 100644
--- a/R/ds.colnames.R
+++ b/R/ds.colnames.R
@@ -53,7 +53,7 @@
 ds.colnames <- function(x=NULL, datasources=NULL) {
 
   datasources <- .resolveDatasources(datasources)
-  .checkDfNameProvided(x)
+  .checkArgProvided(x, "the name of a data.frame or matrix")
 
   cally <- call("colnamesDS", x)
   column_names <- DSI::datashield.aggregate(datasources, cally)
diff --git a/R/ds.completeCases.R b/R/ds.completeCases.R
index acb7c52ec..369d90404 100644
--- a/R/ds.completeCases.R
+++ b/R/ds.completeCases.R
@@ -75,9 +75,7 @@ ds.completeCases <- function(x1=NULL, newobj=NULL, datasources=NULL){
 
   datasources <- .resolveDatasources(datasources)
 
-  if(is.null(x1)){
-    return("Error: x1 must be a character string naming a serverside data.frame, matrix or vector")
-  }
+  .checkArgProvided(x1, "a character string that names a server-side data.frame, matrix or vector")
 
   newobj <- .resolveNewobjName(newobj, paste0(x1,"_complete.cases"))
 
diff --git a/R/ds.contourPlot.R b/R/ds.contourPlot.R
index dac0dbcb1..fcae19b2c 100644
--- a/R/ds.contourPlot.R
+++ b/R/ds.contourPlot.R
@@ -107,12 +107,8 @@ ds.contourPlot <- function(x=NULL, y=NULL, type='combine', show='all', numints=2
 
   datasources <- .resolveDatasources(datasources)
 
-  if(is.null(x)){
-    stop("x=NULL. Please provide the names of two numeric vectors!", call.=FALSE)
-  }
-  if(is.null(y)){
-    stop("y=NULL. Please provide the names of two numeric vectors!", call.=FALSE)
-  }
+  .checkArgProvided(x, "the name of a numeric vector")
+  .checkArgProvided(y, "the name of a numeric vector")
 
   # Save par and setup reseting of par values
   old_par <- graphics::par(no.readonly = TRUE)
@@ -120,7 +116,7 @@ ds.contourPlot <- function(x=NULL, y=NULL, type='combine', show='all', numints=2
   
   # the argument method must be either "smallCellsRule" or "deterministic" or "probabilistic"
   if(method != 'smallCellsRule' & method != 'deterministic' & method != 'probabilistic'){
-    stop('Function argument "method" has to be either "smallCellsRule" or "deterministic" or "probabilistic"', call.=FALSE)
+    .abortInvalidChoice("method", c("smallCellsRule", "deterministic", "probabilistic"))
   }
 
   # extract the variable names to be used as labels in the plot
@@ -352,7 +348,7 @@ ds.contourPlot <- function(x=NULL, y=NULL, type='combine', show='all', numints=2
       # plot a combined contour plot
       graphics::contour(x.zoomed,y.zoomed,z.zoomed, xlab=x.lab, ylab=y.lab, main="Contour Plot of the Pooled Data (zoomed)")
     }else{
-      stop('Function argument "show" has to be either "all" or "zoomed"')
+      .abortInvalidChoice("show", c("all", "zoomed"))
     }
 
   } else if (type=='split') {
@@ -501,7 +497,7 @@ ds.contourPlot <- function(x=NULL, y=NULL, type='combine', show='all', numints=2
           graphics::contour(x.zoomed,y.zoomed,z.zoomed, xlab=x.lab, ylab=y.lab, main=title)
 
         }else{
-          stop('Function argument "show" has to be either "all" or "zoomed"')
+          .abortInvalidChoice("show", c("all", "zoomed"))
         }
 
       }
@@ -589,11 +585,11 @@ ds.contourPlot <- function(x=NULL, y=NULL, type='combine', show='all', numints=2
         graphics::contour(x.zoomed,y.zoomed,z.zoomed, xlab=x.lab, ylab=y.lab, main="Contour Plot of the Pooled Data")
 
       }else{
-        stop('Function argument "show" has to be either "all" or "zoomed"')
+        .abortInvalidChoice("show", c("all", "zoomed"))
       }
 	}
   }else{
-    stop('Function argument "type" has to be either "combine" or "split"')
+    .abortInvalidChoice("type", c("combine", "split"))
   }
 
 }
diff --git a/R/ds.cor.R b/R/ds.cor.R
index 0e44b06d2..d79848931 100644
--- a/R/ds.cor.R
+++ b/R/ds.cor.R
@@ -85,9 +85,7 @@ ds.cor <- function(x=NULL, y=NULL, type="split", datasources=NULL, classConsiste
 
   datasources <- .resolveDatasources(datasources)
 
-  if(is.null(x)){
-    stop("x=NULL. Please provide the name of a matrix or dataframe or the names of two numeric vectors!", call.=FALSE)
-  }
+  .checkArgProvided(x, "the name of a matrix, data.frame or numeric vector")
 
   # name of the studies to be used in the output
   stdnames <- names(datasources)
@@ -164,7 +162,7 @@ ds.cor <- function(x=NULL, y=NULL, type="split", datasources=NULL, classConsiste
 	    n4 <- "Correlation Matrix"
 	    names(results) <- c(n1, n2, n3, n4)
     }else{
-      stop('Function argument "type" has to be either "combine" or "split"', call.=FALSE)
+      .abortInvalidChoice("type", c("combine", "split"))
     }
   }
 
diff --git a/R/ds.corTest.R b/R/ds.corTest.R
index 609ce6d71..4e6ea7525 100644
--- a/R/ds.corTest.R
+++ b/R/ds.corTest.R
@@ -69,15 +69,11 @@ ds.corTest <- function(x=NULL, y=NULL, method="pearson", exact=NULL, conf.level=
 
   datasources <- .resolveDatasources(datasources)
 
-  if(is.null(x)){
-    stop("x=NULL. Please provide the names of the 1st numeric vector!", call.=FALSE)
-  }
-  if(is.null(y)){
-    stop("y=NULL. Please provide the names of the 2nd numeric vector!", call.=FALSE)
-  }
+  .checkArgProvided(x, "the name of the first numeric vector")
+  .checkArgProvided(y, "the name of the second numeric vector")
 
   if(!(method %in% c("pearson", "kendall", "spearman"))){
-    stop('Function argument "method" has to be either "pearson", "kendall" or "spearman"', call.=FALSE)
+    .abortInvalidChoice("method", c("pearson", "kendall", "spearman"))
   }
 
   # call the server side function
@@ -132,7 +128,7 @@ ds.corTest <- function(x=NULL, y=NULL, method="pearson", exact=NULL, conf.level=
         return(out)
       }  
     }else{
-      stop('Function argument "type" has to be either "combine" or "split"', call.=FALSE)
+      .abortInvalidChoice("type", c("combine", "split"))
     }
   }
 
diff --git a/R/ds.cov.R b/R/ds.cov.R
index a7ffac52c..15b4f1181 100644
--- a/R/ds.cov.R
+++ b/R/ds.cov.R
@@ -102,9 +102,7 @@ ds.cov <- function(x=NULL, y=NULL, naAction='pairwise.complete', type="split", d
 
   datasources <- .resolveDatasources(datasources)
 
-  if(is.null(x)){
-    stop("x=NULL. Please provide the name of a matrix or dataframe or the names of two numeric vectors!", call.=FALSE)
-  }
+  .checkArgProvided(x, "the name of a matrix, data.frame or numeric vector")
 
   # name of the studies to be used in the output
   stdnames <- names(datasources)
@@ -195,7 +193,7 @@ ds.cov <- function(x=NULL, y=NULL, naAction='pairwise.complete', type="split", d
       n5 <- "Error message"
       names(results) <- c(n1, n2, n3, n4, n5)
     }else{
-      stop('Function argument "type" has to be either "combine" or "split"')
+      .abortInvalidChoice("type", c("combine", "split"))
     }
   }
 
diff --git a/R/ds.dataFrame.R b/R/ds.dataFrame.R
index c3aea4fb2..802917b63 100644
--- a/R/ds.dataFrame.R
+++ b/R/ds.dataFrame.R
@@ -94,9 +94,7 @@ ds.dataFrame <- function(x=NULL, row.names=NULL, check.rows=FALSE, check.names=T
 
   datasources <- .resolveDatasources(datasources)
 
-  if(is.null(x)){
-    stop("Please provide the name of the list that holds the input vectors!", call.=FALSE)
-  }
+  .checkArgProvided(x, "the name of the list that holds the input vectors")
 
   # create a name by default if user did not provide a name for the new variable
   newobj <- .resolveNewobjName(newobj, "dataframe.newobj")
@@ -105,49 +103,10 @@ ds.dataFrame <- function(x=NULL, row.names=NULL, check.rows=FALSE, check.names=T
 
     # call the internal function that checks the input object(s) is(are) of the same legal class in all studies.
     if(classConsistencyCheck){
-    for(i in 1:length(x)){
-      typ <- checkClass(datasources, x[i])
-      if(!('data.frame' %in% typ) & !('matrix' %in% typ) & !('factor' %in% typ) & !('character' %in% typ) & !('numeric' %in% typ) & !('integer' %in% typ) & !('logical' %in% typ)){
-        stop("Only objects of type 'data.frame', 'matrix', 'numeric', 'integer', 'character', 'factor' and 'logical' are allowed.", call.=FALSE)
-      }
+    .checkObjectClasses(datasources, x)
     }
-    }
-    
-    # check that there are no duplicated column names in the input components
-    for(j in 1:length(datasources)){
-      colNames <- list()
-      for(i in 1:length(x)){
-        typ <- checkClass(datasources, x[i])
-        if(typ %in% c('data.frame', 'matrix')){
-          colNames[[i]] <- ds.colnames(x=x[i], datasources=datasources[j])
-        }
-        if(typ %in% c('factor', 'character', 'numeric', 'integer', 'logical')){
-          colNames[[i]] <- as.character(x[i])
-        }
-        colNames <- unlist(colNames)
-        if(anyDuplicated(colNames) != 0){
-          message("\n Warning: Some column names in study", j, "are duplicated and a suffix '.k' will be added to the kth replicate \n")
-        }  
-      }  
-    } 
     
-    # check that the number of rows is the same in all componets to be cbind
-    for(j in 1:length(datasources)){
-      nrows <- list()
-      for(i in 1:length(x)){
-        typ <- checkClass(datasources, x[i])
-        if(typ %in% c('data.frame', 'matrix')){
-          nrows[[i]] <- ds.dim(x=x[i], type='split', datasources=datasources[j])[[1]][1]
-        }
-        if(typ %in% c('factor', 'character', 'numeric', 'integer', 'logical')){
-          nrows[[i]] <- ds.length(x[i], type='split', datasources=datasources[j])[[1]]
-        }
-      }
-      nrows <- unlist(nrows)
-      if(any(nrows != nrows[1])){
-        stop("The number of rows is not the same in all of the input components", call.=FALSE)
-      }
-    }  
+    .checkMultiObjectConsistency(datasources, x)
     
   }
   
diff --git a/R/ds.dataFrameSubset.R b/R/ds.dataFrameSubset.R
index 46af4e411..a4452fd08 100644
--- a/R/ds.dataFrameSubset.R
+++ b/R/ds.dataFrameSubset.R
@@ -110,9 +110,7 @@ ds.dataFrameSubset<-function(df.name=NULL, V1.name=NULL, V2.name=NULL, Boolean.o
   datasources <- .resolveDatasources(datasources)
 
   # check if user has provided the name of the data.frame to be subsetted
-  if(is.null(df.name)){
-    stop("Please provide the name of the data.frame to be subsetted as a character string: eg 'xxx'", call.=FALSE)
-  }
+  .checkArgProvided(df.name, "the name of the data.frame to subset")
 
   # check if user has provided the name of the column or scalar that holds V1. If not
   # have they instead provided a non.null keep.cols or non.null rm.cols argument
diff --git a/R/ds.densityGrid.R b/R/ds.densityGrid.R
index 965c5cfb2..6b96cc69c 100644
--- a/R/ds.densityGrid.R
+++ b/R/ds.densityGrid.R
@@ -88,13 +88,9 @@ ds.densityGrid <- function(x=NULL, y=NULL, numints=20, type='combine', datasourc
 
   datasources <- .resolveDatasources(datasources)
 
-  if(is.null(x)){
-    stop("Please provide the name of the numeric vector 'x'!", call.=FALSE)
-  }
+  .checkArgProvided(x, "the name of a numeric vector")
 
-  if(is.null(y)){
-    stop("Please provide the name of the numeric vector 'y'!", call.=FALSE)
-  }
+  .checkArgProvided(y, "the name of a numeric vector")
   
   # name of the studies to be used in the plots' titles
   stdnames <- names(datasources)
@@ -165,7 +161,7 @@ ds.densityGrid <- function(x=NULL, y=NULL, numints=20, type='combine', datasourc
       }
       return(grid.density.obj)
     }else{
-      stop('Function argument "type" has to be either "combine" or "split"')
+      .abortInvalidChoice("type", c("combine", "split"))
     }
   }
 
diff --git a/R/ds.dim.R b/R/ds.dim.R
index 3d309e75c..d284eb9a2 100644
--- a/R/ds.dim.R
+++ b/R/ds.dim.R
@@ -82,9 +82,7 @@ ds.dim <- function(x=NULL, type='both', datasources=NULL, classConsistencyCheck=
 
   datasources <- .resolveDatasources(datasources)
 
-  if(is.null(x)){
-    stop("Please provide the name of a data.frame or matrix!", call.=FALSE)
-  }
+  .checkArgProvided(x, "the name of a data.frame or matrix")
 
   ###################################################################################################
   #MODULE: EXTEND "type" argument to include "both" and enable valid aliases                        #
@@ -130,7 +128,7 @@ ds.dim <- function(x=NULL, type='both', datasources=NULL, classConsistencyCheck=
         out <- c(dimensions, pooled.dim)
 		    names(out) <- c(outputnames, paste0('dimensions of ', x, ' in combined studies'))
 	    }else{
-        stop('Function argument "type" has to be either "both", "combine" or "split"')
+        .abortInvalidChoice("type", c("both", "combine", "split"))
       }
     }
   }
diff --git a/R/ds.dmtC2S.R b/R/ds.dmtC2S.R
index f5ec7354c..c520aea0c 100644
--- a/R/ds.dmtC2S.R
+++ b/R/ds.dmtC2S.R
@@ -49,9 +49,7 @@ ds.dmtC2S <- function(dfdata=NA, newobj=NULL, datasources=NULL){
   datasources <- .resolveDatasources(datasources)
 
   # check if a value has been provided for dfdata
-  if(is.null(dfdata)){
-    return("Error: dfdata must be a character string, a numeric vector or a scalar")
-  }
+  .checkArgProvided(dfdata, "a character string, numeric vector or scalar")
 
   # if no value specified for output object, then specify a default
   newobj <- .resolveNewobjName(newobj, "dmt.copied.C2S")
@@ -84,8 +82,7 @@ if(dplyr::is.tbl(dfdata))
 		
   if(!is.matrix(dfdata) && !is.data.frame(dfdata) && !dplyr::is.tbl(dfdata))
 	{
-	   message("\n            FAILED: <dfdata> must either be a data.frame, matrix or tibble")	
-       return('Please respecify')
+	   cli_abort("{.arg dfdata} must be a data.frame, matrix or tibble.")
 	}
 
    inout.object.transmit<-paste0(as.character(inout.object),collapse=",")
diff --git a/R/ds.elspline.R b/R/ds.elspline.R
index b96d8c317..e66daec45 100644
--- a/R/ds.elspline.R
+++ b/R/ds.elspline.R
@@ -30,13 +30,9 @@ ds.elspline <- function(x, n, marginal = FALSE, names = NULL, newobj = NULL, dat
   
   datasources <- .resolveDatasources(datasources)
   
-  if(is.null(x)){
-    stop("Please provide the name of the input variable x!", call.=FALSE)
-  }
+  .checkArgProvided(x, "the name of the input variable")
   
-  if(is.null(n)){
-    stop("Argument 'n' is missing, with no default!", call.=FALSE)
-  }
+  .checkArgProvided(n, "a number of knots")
   
   if(n < 2){
     stop("'n' must be a value greater than or equal to 2!", call.=FALSE)
diff --git a/R/ds.exists.R b/R/ds.exists.R
index e8e809284..bf395d1b8 100644
--- a/R/ds.exists.R
+++ b/R/ds.exists.R
@@ -64,9 +64,7 @@ ds.exists <- function(x=NULL, datasources=NULL){
 
   datasources <- .resolveDatasources(datasources)
 
-  if(is.null(x)){
-    stop("Please provide the name of the input object!", call.=FALSE)
-  }
+  .checkArgProvided(x, "the name of the input object")
 
   # call the server side function that does the job
   cally <- call("exists", x)
diff --git a/R/ds.exp.R b/R/ds.exp.R
index 6ab41780c..19677532e 100644
--- a/R/ds.exp.R
+++ b/R/ds.exp.R
@@ -60,9 +60,7 @@ ds.exp <- function(x=NULL, newobj=NULL, datasources=NULL){
 
   datasources <- .resolveDatasources(datasources)
 
-  if(is.null(x)){
-    stop("Please provide the name of the input object!", call.=FALSE)
-  }
+  .checkArgProvided(x, "the name of the input object")
 
   newobj <- .resolveNewobjName(newobj, "exp.newobj")
 
diff --git a/R/ds.gamlss.R b/R/ds.gamlss.R
index 6a9dd0938..094683277 100644
--- a/R/ds.gamlss.R
+++ b/R/ds.gamlss.R
@@ -85,9 +85,7 @@ ds.gamlss <- function(formula = NULL, sigma.formula = '~1', nu.formula = '~1',
   datasources <- .resolveDatasources(datasources)
 
   # verify that 'formula' was set
-  if(is.null(formula)){
-    stop(" Please provide a valid formula!", call.=FALSE)
-  }
+  .checkArgProvided(formula, "a valid formula")
   
   formula <- gsub("(", "left_parenthesis", formula, fixed = TRUE)
   formula <- gsub(")", "right_parenthesis", formula, fixed = TRUE)
@@ -125,7 +123,7 @@ ds.gamlss <- function(formula = NULL, sigma.formula = '~1', nu.formula = '~1',
   
   # check if method is either 'RS', 'CG' or 'mixed
   if(!(method %in% c("RS", "CG", "mixed"))){
-    stop("Argument 'method' must be either 'RS', 'CG' or 'mixed'", call.=FALSE)
+    .abortInvalidChoice("method", c("RS", "CG", "mixed"))
   }
   
   control <- paste0(as.character(control), collapse=",")
diff --git a/R/ds.getWGSR.R b/R/ds.getWGSR.R
index a95dd55c1..cebf04496 100644
--- a/R/ds.getWGSR.R
+++ b/R/ds.getWGSR.R
@@ -105,20 +105,14 @@ ds.getWGSR <- function(sex=NULL, firstPart=NULL, secondPart=NULL, index=NULL, st
   
   datasources <- .resolveDatasources(datasources)
 
-  if(is.null(sex)){
-    stop("Please provide the column name of the 'sex' variable!", call.=FALSE)
-  }
+  .checkArgProvided(sex, "the name of the sex column")
   
-  if(is.null(firstPart)){
-    stop("Please provide the column name of the 'firstPart' variable!", call.=FALSE)
-  }
+  .checkArgProvided(firstPart, "the name of the column that holds the first part")
   
-  if(is.null(secondPart)){
-    stop("Please provide the column name of the 'secondPart' variable!", call.=FALSE)
-  }
+  .checkArgProvided(secondPart, "the name of the column that holds the second part")
   
   if(!any(index %in% c("bfa", "hca", "hfa", "lfa", "mfa", "ssa", "tsa", "wfa", "wfh", "wfl"))){
-    stop("Please provide a correct abbreviation for the index!", call.=FALSE)
+    .abortInvalidChoice("index", c("bfa", "hca", "hfa", "lfa", "mfa", "ssa", "tsa", "wfa", "wfh", "wfl"))
   }
   
   # If 'thirdPart' (age) is missing for BMI-for-age return an error message
diff --git a/R/ds.glm.R b/R/ds.glm.R
index 6d9be8d9d..2c068376c 100644
--- a/R/ds.glm.R
+++ b/R/ds.glm.R
@@ -325,26 +325,16 @@ ds.glm <- function(formula=NULL, data=NULL, family=NULL, offset=NULL, weights=NU
   datasources <- .resolveDatasources(datasources)
 
   # verify that 'formula' was set
-  if(is.null(formula)){
-    stop(" Please provide a valid regression formula!", call.=FALSE)
-  }
+  .checkArgProvided(formula, "a valid regression formula")
 
   # check if user gave offset or weights directly in formula, if so the argument 'offset' or 'weights'
   # to provide name of offset or weights variable
-  if(sum(as.numeric(grepl('offset', formula, ignore.case=TRUE)))>0 ||
-     sum(as.numeric(grepl('weights', formula, ignore.case=TRUE)))>0){
-       message("\n\n WARNING: you may have specified an offset or regression weights")
-       message("\n as part of the model formula. In ds.glm (unlike the usual glm in R)")
-       message("\n you must specify an offset or weights separately from the formula")
-       message("\n using the offset or weights argument.\n\n")
-	}
+  .warnOffsetInFormula(formula)
 
   formula <- stats::as.formula(formula)
 
   # check that 'family' was set
-  if(is.null(family)){
-    stop(" Please provide a valid 'family' argument!", call.=FALSE)
-  }
+  .checkArgProvided(family, "a valid family")
 
   # beginning of optional checks - the process stops if any of these checks fails #
   if(checks){
@@ -426,36 +416,17 @@ ds.glm <- function(formula=NULL, data=NULL, family=NULL, offset=NULL, weights=NU
   errorMessage <- as.matrix(errorMessage)
   dimnames(errorMessage) <- list(names(datasources), "ERROR MESSAGES")
   
-  output.blocked.information.1 <- "MODEL FITTING TERMINATED AT FIRST ITERATION:"
-  output.blocked.information.2 <- "Any values of 1 in the following tables denote potential disclosure risks"
-  output.blocked.information.3 <- "please use the argument <datasources> to include only valid studies."
-  output.blocked.information.4 <- "Errors by study are as follows:"
 
   if(sum.y.invalid>0||sum.Xpar.invalid>0||sum.w.invalid>0||sum.o.invalid>0||sum.glm.saturation.invalid>0||at.least.one.study.data.error==1){
-	  message("\n\nMODEL FITTING TERMINATED AT FIRST ITERATION:\n",
-            "Any values of 1 in the following tables denote potential disclosure risks\n",
-		        "please use the argument <datasources> to include only valid studies.\n",
-		        "Errors by study are as follows:\n")
-		message(as.matrix(y.invalid))
-		message(as.matrix(Xpar.invalid))
-		message(as.matrix(w.invalid))
-		message(as.matrix(o.invalid))
-		message(as.matrix(glm.saturation.invalid))
-		message(as.matrix(errorMessage))
-
-	  return(list(
-      		    output.blocked.information.1,
-      		    output.blocked.information.2,
-      		    output.blocked.information.3,
-      		    output.blocked.information.4,
-      				y.vector.error=y.invalid,
-              X.matrix.error=Xpar.invalid,
-              weight.vector.error=w.invalid,
-              offset.vector.error=o.invalid,
-              glm.overparameterized=glm.saturation.invalid,
-              errorMessage=errorMessage
-          ))
-		stop("DATA ERROR")
+	  cli_inform(c("Model fitting terminated at the first iteration.", "i" = "Values of 1 in the following tables denote potential disclosure risks.", "*" = "Use {.arg datasources} to include only valid studies."))
+		cli_verbatim(utils::capture.output(as.matrix(y.invalid)))
+		cli_verbatim(utils::capture.output(as.matrix(Xpar.invalid)))
+		cli_verbatim(utils::capture.output(as.matrix(w.invalid)))
+		cli_verbatim(utils::capture.output(as.matrix(o.invalid)))
+		cli_verbatim(utils::capture.output(as.matrix(glm.saturation.invalid)))
+		cli_verbatim(utils::capture.output(as.matrix(errorMessage)))
+
+		cli_abort("Can't fit the model because of a data error.")
   }
 
    beta.vect.next <- rep(0, num.par.glm)
@@ -506,34 +477,9 @@ ds.glm <- function(formula=NULL, data=NULL, family=NULL, offset=NULL, weights=NU
   dimnames(errorMessage2) <- list(names(datasources), "ERROR MESSAGES")
 
   if(disclosure.risk.total>0){
-	message("Potential disclosure risk in y.vect, X.mat, w.vect or offset \n",
-	        "or model overparameterized in at least one study.\n",
-			"In addition clientside function appears to have been modified\n",
-			"to avoid traps in first serverside function.\n",
-			"Score vectors and information matrices therefore destroyed in all invalid studies\n",
-			"and model fitting terminated. This error is recorded in the log file but\n",
-			"please report it to the DataSHIELD team as we need to understand how\n",
-			"the controlled shutdown traps in glmDS1 have been circumvented\n\n")
-
-	output.blocked.information.1<-"Potential disclosure risk in y.vect, X.mat, w.vect or offset"
-	output.blocked.information.2<-"or model overparameterized in at least one study."
-	output.blocked.information.3<-"In addition clientside function appears to have been modified"
-	output.blocked.information.4<-"to avoid disclosure traps in first serverside function."
-	output.blocked.information.5<-"Score vectors and information matrices therefore destroyed in all invalid studies"
-	output.blocked.information.6<-"and model fitting terminated. This error is recorded in the log file but"
-	output.blocked.information.7<-"please also report it to the DataSHIELD team as we need to understand how"
-	output.blocked.information.8<-"the controlled shutdown traps in glmDS1 have been circumvented."
-
-
-        return(list(output.blocked.information.1,
-			output.blocked.information.2,
-			output.blocked.information.3,
-			output.blocked.information.4,
-			output.blocked.information.5,
-			output.blocked.information.6,
-			output.blocked.information.7,
-			output.blocked.information.8
-	            ))
+	cli_inform(c("Potential disclosure risk in y.vect, X.mat, w.vect or offset, or the model is overparameterized, in at least one study.", "x" = "The client-side function also appears to have been modified to avoid traps in the first server-side function.", "i" = "Score vectors and information matrices were destroyed in all invalid studies and model fitting was terminated.", "*" = "This error is recorded in the log file. Please report it to the DataSHIELD team, as we need to understand how the controlled shutdown traps in {.fn glmDS1} were circumvented."))
+
+	cli_abort("Can't fit the model because of a potential disclosure risk.")
 	}
 
 
diff --git a/R/ds.glmPredict.R b/R/ds.glmPredict.R
index 820d0ff51..e967d1e36 100644
--- a/R/ds.glmPredict.R
+++ b/R/ds.glmPredict.R
@@ -131,18 +131,16 @@ ds.glmPredict <- function(glmname = NULL, newdataname = NULL, output.type = "res
   datasources <- .resolveDatasources(datasources)
 
   # check that <glmname> is set
-  if(is.null(glmname)){
-	  stop("<glmname> is not set, please specify it as a character string containing the name of a valid glm class object on the serverside", call.=FALSE)
-  }
+  .checkArgProvided(glmname, "the name of a glm object on the server")
 
   # check that <output.type> is correctly set
   if((output.type!="link") && (output.type!="response") && (output.type!="terms")){
-	  stop("<output.type> is not correctly set, please specify it as one of three character strings: 'link', 'response', or 'terms'", call.=FALSE)
+	  .abortInvalidChoice("output.type", c("link", "response", "terms"))
   }
 
   # check that <na.action> is correctly set
   if((na.action!="na.fail")&&(na.action!="na.omit")&&(na.action!="na.exclude")&&(na.action!="na.pass")){
-	  stop("<na.action> is not correctly set, please specify it as one of four character strings: 'na.fail', 'na.omit', 'na.exclude' or 'na.pass'", call.=FALSE)
+	  .abortInvalidChoice("na.action", c("na.fail", "na.omit", "na.exclude", "na.pass"))
   }
 
   # provide value for newobj if none specified
diff --git a/R/ds.glmSLMA.R b/R/ds.glmSLMA.R
index 62d1b278c..239cf1ac7 100644
--- a/R/ds.glmSLMA.R
+++ b/R/ds.glmSLMA.R
@@ -373,28 +373,17 @@ ds.glmSLMA<-function(formula=NULL, family=NULL, offset=NULL, weights=NULL, combi
   datasources <- .resolveDatasources(datasources)
 
   # verify that 'formula' was set
-  if(is.null(formula)){
-    stop(" Please provide a valid regression formula!", call.=FALSE)
-  }
+  .checkArgProvided(formula, "a valid regression formula")
 
 # check if user gave offset or weights directly in formula, if so the argument 'offset' or 'weights'
 # to provide name of offset or weights variable
-    if(sum(as.numeric(grepl('offset', formula, ignore.case=TRUE)))>0 ||
-       sum(as.numeric(grepl('weights', formula, ignore.case=TRUE)))>0)
-{
-       message("\n\n WARNING: you may have specified an offset or regression weights")
-       message("\n as part of the model formula. In ds.glm (unlike the usual glm in R)")
-       message("\n you must specify an offset or weights separately from the formula")
-       message("\n using the offset or weights argument.\n\n")
-}
+    .warnOffsetInFormula(formula)
 
   formula <- stats::as.formula(formula)
 
 
   # check that 'family' was set
-  if(is.null(family)){
-    stop(" Please provide a valid 'family' argument!", call.=FALSE)
-  }
+  .checkArgProvided(family, "a valid family")
 
 #####################
   #if family is non-standard (i.e.family includes calls to either link or variance) convert to transmittable form:
@@ -531,31 +520,20 @@ dimnames(errorMessage)<-list(names(datasources),"ERROR MESSAGES")
 
 
 
-output.blocked.information.1<-"EVERY STUDY HAS DATA THAT COULD BE POTENTIALLY DISCLOSIVE UNDER THE CURRENT MODEL:"
-output.blocked.information.2<-"Any values of 1 in the following tables denote potential disclosure risks."
-output.blocked.information.3<-"Please use the argument <datasources> to include only valid studies."
-output.blocked.information.4<-"Errors by study are as follows:"
 
 
 #CASE 1 - NO STUDIES VALID
 if(!at.least.one.study.valid)
 	{
-	message("\n\nEVERY STUDY HAS DATA THAT COULD BE POTENTIALLY DISCLOSIVE UNDER THE CURRENT MODEL:\n",
-	    "Any values of 1 in the following tables denote potential disclosure risks.\n",
-		"Errors by study are as follows:\n")
-
-
-    return(list(
-		    output.blocked.information.1,
-		    output.blocked.information.2,
-		    output.blocked.information.4,
-				y.vector.error=y.invalid,
-                X.matrix.error=Xpar.invalid,
-                weight.vector.error=w.invalid,
-                offset.vector.error=o.invalid,
-                glm.overparameterized=glm.saturation.invalid,
-	        errorMessage=errorMessage
-                ))
+	cli_inform(c("Every study has data that could be potentially disclosive under the current model.", "i" = "Values of 1 in the following tables denote potential disclosure risks."))
+
+	cli_verbatim(utils::capture.output(as.matrix(y.invalid)))
+	cli_verbatim(utils::capture.output(as.matrix(Xpar.invalid)))
+	cli_verbatim(utils::capture.output(as.matrix(w.invalid)))
+	cli_verbatim(utils::capture.output(as.matrix(o.invalid)))
+	cli_verbatim(utils::capture.output(as.matrix(glm.saturation.invalid)))
+	cli_verbatim(utils::capture.output(as.matrix(errorMessage)))
+	cli_abort("Can't fit the model because every study has data that could be disclosive.")
 	}
 
 #CASE 2 - AT LEAST ONE STUDY VALID AND AT LEAST ONE INVALID
diff --git a/R/ds.glmerSLMA.R b/R/ds.glmerSLMA.R
index f9d84c839..0dfe036a5 100644
--- a/R/ds.glmerSLMA.R
+++ b/R/ds.glmerSLMA.R
@@ -250,27 +250,16 @@ ds.glmerSLMA <- function(formula=NULL, offset=NULL, weights=NULL, combine.with.m
   datasources <- .resolveDatasources(datasources)
 
   # verify that 'formula' was set
-  if(is.null(formula)){
-    stop(" Please provide a valid regression formula!", call.=FALSE)
-  }
+  .checkArgProvided(formula, "a valid regression formula")
   
   # check if user gave offset or weights directly in formula, if so the argument 'offset' or 'weights'
   # to provide name of offset or weights variable
-  if(sum(as.numeric(grepl('offset', formula, ignore.case=TRUE)))>0 ||
-     sum(as.numeric(grepl('weights', formula, ignore.case=TRUE)))>0)
-  {
-    message("\n\n WARNING: you may have specified an offset or regression weights")
-    message("\n as part of the model formula. In ds.glm (unlike the usual glm in R)")
-    message("\n you must specify an offset or weights separately from the formula")
-    message("\n using the offset or weights argument.\n\n")
-  }
+  .warnOffsetInFormula(formula)
   
   formula <- stats::as.formula(formula)
   
   # check that 'family' was set
-  if(is.null(family)){
-    stop(" Please provide a valid 'family' argument!", call.=FALSE)
-  }
+  .checkArgProvided(family, "a valid family")
   
   # beginning of optional checks - the process stops if any of these checks fails #
   if(checks){
@@ -311,9 +300,7 @@ ds.glmerSLMA <- function(formula=NULL, offset=NULL, weights=NULL, combine.with.m
   
   if(!is.null(control_type) && is.null(control_value))
   {
-    errorMessage.cv<-"ERROR: if control_type is non-null, you must specify a valid control_value eg control_value<-1.0e-7"
-    #	print(errorMessage.cv)
-    return(list(errorMessage=errorMessage.cv))
+    cli_abort(c("{.arg control_value} must be set when {.arg control_type} is set.", "i" = "For example, {.code control_value = 1.0e-7}."))
   }
   
   if(!is.null(control_value))
diff --git a/R/ds.heatmapPlot.R b/R/ds.heatmapPlot.R
index 85369097f..645b76764 100644
--- a/R/ds.heatmapPlot.R
+++ b/R/ds.heatmapPlot.R
@@ -155,13 +155,9 @@ ds.heatmapPlot <- function(x=NULL, y=NULL, type="combine", show="all", numints=2
 
   datasources <- .resolveDatasources(datasources)
 
-  if(is.null(x)){
-    stop("x=NULL. Please provide the names of the 1st numeric vector!", call.=FALSE)
-  }
+  .checkArgProvided(x, "the name of the first numeric vector")
 
-  if(is.null(y)){
-    stop("y=NULL. Please provide the names of the 2nd numeric vector!", call.=FALSE)
-  }
+  .checkArgProvided(y, "the name of the second numeric vector")
 
   # Save par and setup reseting of par values
   old_par <- graphics::par(no.readonly = TRUE)
@@ -169,7 +165,7 @@ ds.heatmapPlot <- function(x=NULL, y=NULL, type="combine", show="all", numints=2
   
   # the argument method must be either "smallCellsRule" or "deterministic" or "probabilistic"
   if(method != 'smallCellsRule' & method != 'deterministic' & method != 'probabilistic'){
-    stop('Function argument "method" has to be either "smallCellsRule" or "deterministic" or "probabilistic"', call.=FALSE)
+    .abortInvalidChoice("method", c("smallCellsRule", "deterministic", "probabilistic"))
   }
 
   # prepare the axis labels
@@ -404,7 +400,7 @@ ds.heatmapPlot <- function(x=NULL, y=NULL, type="combine", show="all", numints=2
       fields::image.plot(x.zoomed, y.zoomed, z.zoomed, xlab=x.lab, ylab=y.lab, main="Heatmap Plot of the Pooled Data (zoomed)")
 
     }else{
-       stop('Function argument "show" has to be either "all" or "zoomed"')
+       .abortInvalidChoice("show", c("all", "zoomed"))
     }
   } else if (type=='split') {
 
@@ -557,7 +553,7 @@ ds.heatmapPlot <- function(x=NULL, y=NULL, type="combine", show="all", numints=2
            fields::image.plot(x.zoomed, y.zoomed, z.zoomed, xlab = x.lab, ylab = y.lab, main = title)
 
          }else{
-           stop('Function argument "show" has to be either "all" or "zoomed"')
+           .abortInvalidChoice("show", c("all", "zoomed"))
          }
        }
 
@@ -651,11 +647,11 @@ ds.heatmapPlot <- function(x=NULL, y=NULL, type="combine", show="all", numints=2
          fields::image.plot(x.zoomed, y.zoomed, z.zoomed, xlab = x.lab, ylab = y.lab, main = "Heatmap Plot of the Pooled Data")
 
        }else{
-         stop('Function argument "show" has to be either "all" or "zoomed"')
+         .abortInvalidChoice("show", c("all", "zoomed"))
        }
      }
 
    }else{
-     stop('Function argument "type" has to be either "combine" or "split"')
+     .abortInvalidChoice("type", c("combine", "split"))
    }
 }
diff --git a/R/ds.hetcor.R b/R/ds.hetcor.R
index be3e3f790..5fa2da67f 100644
--- a/R/ds.hetcor.R
+++ b/R/ds.hetcor.R
@@ -34,9 +34,7 @@ ds.hetcor <- function(data=NULL, ML=TRUE, std.err=TRUE, bins=4, pd=TRUE, use="co
   
   datasources <- .resolveDatasources(datasources)
   
-  if(is.null(data)){
-    stop("Please provide the name of the input object!", call.=FALSE)
-  }
+  .checkArgProvided(data, "the name of the input object")
   
   calltext <- call('hetcorDS', data, ML, std.err, bins, pd, use)
   output <- DSI::datashield.aggregate(datasources, calltext)
diff --git a/R/ds.histogram.R b/R/ds.histogram.R
index 611f8dcd6..9737dcc4b 100644
--- a/R/ds.histogram.R
+++ b/R/ds.histogram.R
@@ -157,9 +157,7 @@ ds.histogram <- function(x=NULL, type="split", num.breaks=10, method="smallCells
 
   datasources <- .resolveDatasources(datasources)
 
-  if(is.null(x)){
-    stop("Please provide the name of the input vector!", call.=FALSE)
-  }
+  .checkArgProvided(x, "the name of the input vector")
 
   # Save par and setup reseting of par values
   old_par <- graphics::par(no.readonly = TRUE)
@@ -167,12 +165,12 @@ ds.histogram <- function(x=NULL, type="split", num.breaks=10, method="smallCells
 
   # the argument vertical.axis must be "Frequency" or "Density"
   if(vertical.axis != 'Frequency' & vertical.axis != 'Density'){
-    stop('Function argument "vertical.axis" has to be either "Frequency" or "Density"', call.=FALSE)
+    .abortInvalidChoice("vertical.axis", c("Frequency", "Density"))
   }
 
   # the argument method must be either "smallCellsRule" or "deterministic" or "probabilistic"
   if(method != 'smallCellsRule' & method != 'deterministic' & method != 'probabilistic'){
-    stop('Function argument "method" has to be either "smallCellsRule" or "deterministic" or "probabilistic"', call.=FALSE)
+    .abortInvalidChoice("method", c("smallCellsRule", "deterministic", "probabilistic"))
   }
 
   # name of the studies to be used in the plots' titles
@@ -277,7 +275,7 @@ ds.histogram <- function(x=NULL, type="split", num.breaks=10, method="smallCells
         return(hist.objs[[1]])
       }
     }else{
-      stop('Function argument "type" has to be either "combine" or "split"')
+      .abortInvalidChoice("type", c("combine", "split"))
     }
   }
 
diff --git a/R/ds.igb_standards.R b/R/ds.igb_standards.R
index 5213bb811..4819a245f 100644
--- a/R/ds.igb_standards.R
+++ b/R/ds.igb_standards.R
@@ -45,28 +45,22 @@ ds.igb_standards <- function(gagebrth=NULL, z=0, p=50, val=NULL, var=NULL, sex=N
   datasources <- .resolveDatasources(datasources)
   
   # check if user has provided the name of the input variables
-  if(is.null(gagebrth)){
-    stop("Please provide the name of the gagebrth variable", call.=FALSE)
-  }
-  if(is.null(sex)){
-    stop("Please provide the name of the sex variable", call.=FALSE)
-  }
+  .checkArgProvided(gagebrth, "the name of the gestational age variable")
+  .checkArgProvided(sex, "the name of the sex variable")
   
   # check if the provided fun is valid
   if(!(fun %in% c("igb_centile2value","igb_zscore2value","igb_value2zscore","igb_value2centile"))){
-    stop("Please provide a valid fun", call.=FALSE)
+    .abortInvalidChoice("fun", c("igb_centile2value", "igb_zscore2value", "igb_value2zscore", "igb_value2centile"))
   }
   
   # check if val is provided if fun is either igb_value2zscore or igb_value2centile
   if(fun %in% c("igb_value2zscore","igb_value2centile")){
-    if(is.null(val)){
-      stop("Please provide the name of the val variable", call.=FALSE)
-    }
+    .checkArgProvided(val, "the name of the value variable")
   }
   
   # check if the provided var is valid
   if(!(var %in% c("lencm", "wtkg", "hcircm", "wlr"))){
-    stop("Please provide a valid var", call.=FALSE)
+    .abortInvalidChoice("var", c("lencm", "wtkg", "hcircm", "wlr"))
   }
   
   # if no output variable specified then provide a default name
diff --git a/R/ds.isNA.R b/R/ds.isNA.R
index 2c4cf51ff..c6e5b1ed2 100644
--- a/R/ds.isNA.R
+++ b/R/ds.isNA.R
@@ -61,9 +61,7 @@ ds.isNA <- function(x=NULL, datasources=NULL, classConsistencyCheck=TRUE){
 
   datasources <- .resolveDatasources(datasources)
 
-  if(is.null(x)){
-    stop("Please provide the name of the input vector!", call.=FALSE)
-  }
+  .checkArgProvided(x, "the name of the input vector")
 
   stdnames <- names(datasources)
   xnames <- extract(x)
diff --git a/R/ds.isValid.R b/R/ds.isValid.R
index 3ad72526c..7527a6f90 100644
--- a/R/ds.isValid.R
+++ b/R/ds.isValid.R
@@ -61,9 +61,7 @@ ds.isValid <- function(x=NULL, datasources=NULL, classConsistencyCheck=TRUE){
 
   datasources <- .resolveDatasources(datasources)
 
-  if(is.null(x)){
-    stop("Please provide the name of the input vector!", call.=FALSE)
-  }
+  .checkArgProvided(x, "the name of the input vector")
 
   # call the server side function that does the job and return its output
   cally <- call("isValidDS", x)
diff --git a/R/ds.kurtosis.R b/R/ds.kurtosis.R
index 35ddfe78e..95ef39802 100644
--- a/R/ds.kurtosis.R
+++ b/R/ds.kurtosis.R
@@ -31,9 +31,7 @@ ds.kurtosis <- function(x=NULL, method=1, type='both', datasources=NULL, classCo
 
   datasources <- .resolveDatasources(datasources)
 
-  if(is.null(x)){
-    stop("Please provide the name of the input vector!", call.=FALSE)
-  }
+  .checkArgProvided(x, "the name of the input vector")
   
   if(!all(method %in% c(1,2,3))){
     stop("method must be an integer between 1 and 3", call.=FALSE)
@@ -44,7 +42,7 @@ ds.kurtosis <- function(x=NULL, method=1, type='both', datasources=NULL, classCo
   if(type == 'split' | type == 'splits' | type == 's') type <- 'split'
   if(type == 'both' | type == 'b' ) type <- 'both'
   if(type != 'combine' & type != 'split' & type != 'both'){
-    stop('Function argument "type" has to be either "both", "combine" or "split"', call.=FALSE)
+    .abortInvalidChoice("type", c("both", "combine", "split"))
   }
   
   if (type=='split' | type=='both'){
diff --git a/R/ds.length.R b/R/ds.length.R
index 74cec9f5e..4cc1edb2a 100644
--- a/R/ds.length.R
+++ b/R/ds.length.R
@@ -77,9 +77,7 @@ ds.length <- function(x=NULL, type='both', datasources=NULL, classConsistencyChe
 
   datasources <- .resolveDatasources(datasources)
 
-  if(is.null(x)){
-    stop("Please provide the name of the input object!", call.=FALSE)
-  }
+  .checkArgProvided(x, "the name of the input object")
 
   ###################################################################################################
   # MODULE: EXTEND "type" argument to include "both" and enable valid aliases                      #
@@ -87,7 +85,7 @@ ds.length <- function(x=NULL, type='both', datasources=NULL, classConsistencyChe
   if(type == 'split' | type == 'splits' | type == 's') type <- 'split'                              #
   if(type == 'both' | type == 'b' ) type <- 'both'                                                  #
   if(type != 'combine' & type != 'split' & type != 'both'){                                         #
-    stop('Function argument "type" has to be either "both", "combine" or "split"', call.=FALSE)     #
+    .abortInvalidChoice("type", c("both", "combine", "split"))     #
   }
 
   # call the server-side function
@@ -123,7 +121,7 @@ ds.length <- function(x=NULL, type='both', datasources=NULL, classConsistencyChe
         out <- c(lengths, pooled.length)
         names(out) <- c(outputnames, paste0('total length of ', x, ' in all studies combined'))
       }else{
-        stop('Function argument "type" has to be either "both", "combine" or "split"')
+        .abortInvalidChoice("type", c("both", "combine", "split"))
       }
     }
   }
diff --git a/R/ds.levels.R b/R/ds.levels.R
index 8232f601f..f55adf91c 100644
--- a/R/ds.levels.R
+++ b/R/ds.levels.R
@@ -61,9 +61,7 @@ ds.levels <- function(x=NULL, datasources=NULL){
 
   datasources <- .resolveDatasources(datasources)
 
-  if(is.null(x)){
-    stop("Please provide the name of the input vector!", call.=FALSE)
-  }
+  .checkArgProvided(x, "the name of the input vector")
 
   cally <- call("levelsDS", x)
   results <- DSI::datashield.aggregate(datasources, cally)
diff --git a/R/ds.lexis.R b/R/ds.lexis.R
index 2ae033685..74aaf3b80 100644
--- a/R/ds.lexis.R
+++ b/R/ds.lexis.R
@@ -206,19 +206,13 @@ ds.lexis<-function(data=NULL, intervalWidth=NULL, idCol=NULL, entryCol=NULL, exi
   datasources <- .resolveDatasources(datasources)
 
   # check if user have provided the name of the column that holds the subject ids
-  if(is.null(idCol)){
-    stop("Please provide the name of the column that holds the subject IDs!", call.=FALSE)
-  }
+  .checkArgProvided(idCol, "the name of the column that holds subject IDs")
 
   # check if user have provided the name of the column that holds failure information
-  if(is.null(statusCol)){
-    stop("Please provide the name of the column that holds 'failure' information!", call.=FALSE)
-  }
+  .checkArgProvided(statusCol, "the name of the column that holds failure information")
 
   # check if user have provided the name of the column that holds exit times
-  if(is.null(exitCol)){
-    stop("Please provide the name of the column that holds the exit times (i.e. end of follow up time)!", call.=FALSE)
-  }
+  .checkArgProvided(exitCol, "the name of the column that holds exit times")
 
   # if no valid value provided for 'intervalWidth' instruct user to specify one
   if(any(is.null(intervalWidth))||any(is.na(intervalWidth))||any(intervalWidth==0)){
diff --git a/R/ds.list.R b/R/ds.list.R
index 9209291d7..b75dac9f8 100644
--- a/R/ds.list.R
+++ b/R/ds.list.R
@@ -58,9 +58,7 @@ ds.list <- function(x=NULL, newobj=NULL, datasources=NULL, classConsistencyCheck
 
   datasources <- .resolveDatasources(datasources)
 
-  if(is.null(x)){
-    stop("x=NULL. Please provide the names of the objects to coerce into a list!", call.=FALSE)
-  }
+  .checkArgProvided(x, "the names of the objects to coerce into a list")
 
   # create a name by default if user did not provide a name for the new variable
   newobj <- .resolveNewobjName(newobj, "list.newobj")
diff --git a/R/ds.lmerSLMA.R b/R/ds.lmerSLMA.R
index 400160a1f..5c42ab342 100644
--- a/R/ds.lmerSLMA.R
+++ b/R/ds.lmerSLMA.R
@@ -209,20 +209,11 @@ ds.lmerSLMA <- function(formula=NULL, offset=NULL, weights=NULL, combine.with.me
   datasources <- .resolveDatasources(datasources)
 
   # verify that 'formula' was set
-  if(is.null(formula)){
-    stop(" Please provide a valid regression formula!", call.=FALSE)
-  }
+  .checkArgProvided(formula, "a valid regression formula")
   
   # check if user gave offset or weights directly in formula, if so the argument 'offset' or 'weights'
   # to provide name of offset or weights variable
-  if(sum(as.numeric(grepl('offset', formula, ignore.case=TRUE)))>0 ||
-     sum(as.numeric(grepl('weights', formula, ignore.case=TRUE)))>0)
-  {
-    message("\n\n WARNING: you may have specified an offset or regression weights")
-    message("\n as part of the model formula. In ds.glm (unlike the usual glm in R)")
-    message("\n you must specify an offset or weights separately from the formula")
-    message("\n using the offset or weights argument.\n\n")
-  }
+  .warnOffsetInFormula(formula)
   
   formula <- stats::as.formula(formula)
   
@@ -255,8 +246,7 @@ ds.lmerSLMA <- function(formula=NULL, offset=NULL, weights=NULL, combine.with.me
 
  if(!is.null(control_type) && is.null(control_value))
 	{
-	errorMessage.cv<-"ERROR: if control_type is non-null, you must specify a valid control_value eg control_value<-1.0e-7"
-	return(list(errorMessage=errorMessage.cv))
+	cli_abort(c("{.arg control_value} must be set when {.arg control_type} is set.", "i" = "For example, {.code control_value = 1.0e-7}."))
 	}
 
 	if(!is.null(control_value))
@@ -273,9 +263,7 @@ ds.lmerSLMA <- function(formula=NULL, offset=NULL, weights=NULL, combine.with.me
  
  if(!is.null(optimizer)&&optimizer!="nloptwrap")
         {
-	errorMessage.opt<-"ERROR: the only optimizer currently available for lmer is 'nloptwrap', please respecify"
-	message("\n",errorMessage.opt,"\n")
-	return(list(errorMessage=errorMessage.opt))
+	.abortInvalidChoice("optimizer", "nloptwrap")
 	}
 
  
diff --git a/R/ds.log.R b/R/ds.log.R
index 145ec93e5..b9663f070 100644
--- a/R/ds.log.R
+++ b/R/ds.log.R
@@ -60,9 +60,7 @@ ds.log <- function(x=NULL, base=exp(1), newobj=NULL, datasources=NULL){
 
   datasources <- .resolveDatasources(datasources)
 
-  if(is.null(x)){
-    stop("Please provide the name of the input vector!", call.=FALSE)
-  }
+  .checkArgProvided(x, "the name of the input vector")
 
   newobj <- .resolveNewobjName(newobj, "log.newobj")
 
diff --git a/R/ds.ls.R b/R/ds.ls.R
index 4df9ad677..677845b0f 100644
--- a/R/ds.ls.R
+++ b/R/ds.ls.R
@@ -160,10 +160,7 @@ if(!is.null(transmit.object))
 
 			if(original.code.problem==TRUE)
 			{
-	#			return.message<-paste0("Warning: Code replacing wildcard (i.e. '",replacement string,"' appears in your original code -please respecify")
-				return.message<-paste0("Warning: Code replacing wildcard (i.e. '",input.string,
-				"') is '",replacement.string,"' but this appears in your original search filter string - please respecify")
-				return(return.message)
+				cli_abort(c("The code that replaces the wildcard ({.val {input.string}}) is {.val {replacement.string}}, which also appears in your search filter.", "i" = "Respecify the filter."))
 			}
 		}
 	}
diff --git a/R/ds.lspline.R b/R/ds.lspline.R
index 1cfc3cd8f..b7c005910 100644
--- a/R/ds.lspline.R
+++ b/R/ds.lspline.R
@@ -27,13 +27,9 @@ ds.lspline <- function(x, knots = NULL, marginal = FALSE, names = NULL, newobj =
   
   datasources <- .resolveDatasources(datasources)
   
-  if(is.null(x)){
-    stop("Please provide the name of the input variable x!", call.=FALSE)
-  }
+  .checkArgProvided(x, "the name of the input variable")
   
-  if(is.null(knots)){
-    stop("Please provide a vector of knots!", call.=FALSE)
-  }
+  .checkArgProvided(knots, "a vector of knots")
   
   # create a name by default if user did not provide a name for the new variable
   newobj <- .resolveNewobjName(newobj, "lspline.newobj")
diff --git a/R/ds.make.R b/R/ds.make.R
index e469087c1..c396090f3 100644
--- a/R/ds.make.R
+++ b/R/ds.make.R
@@ -134,9 +134,7 @@ ds.make<-function(toAssign=NULL, newobj=NULL, datasources=NULL){
 
   datasources <- .resolveDatasources(datasources)
 
-  if(is.null(toAssign)){
-    stop("Please give the name of object to assign or an expression to evaluate and assign.!\n", call.=FALSE)
-  }
+  .checkArgProvided(toAssign, "the name of the object to assign or an expression to evaluate")
   
   # create a name by default if user did not provide a name for the new variable
   newobj <- .resolveNewobjName(newobj, "make.newobj")
diff --git a/R/ds.matrix.R b/R/ds.matrix.R
index 442fa5154..01c62683f 100644
--- a/R/ds.matrix.R
+++ b/R/ds.matrix.R
@@ -148,9 +148,7 @@ ds.matrix <- function(mdata = NA, from="clientside.scalar", nrows.scalar=NULL, n
   datasources <- .resolveDatasources(datasources)
 
   # check if a value has been provided for mdata
-  if(is.null(mdata)){
-    return("Error: mdata must be a character string, a numeric vector or a scalar")
-  }
+  .checkArgProvided(mdata, "a character string, numeric vector or scalar")
 
   # if no value spcified for output object, then specify a default
   newobj <- .resolveNewobjName(newobj, "matrix.newobj")
@@ -159,9 +157,7 @@ ds.matrix <- function(mdata = NA, from="clientside.scalar", nrows.scalar=NULL, n
   #Check that valid from has been specified
   if(from!="serverside.vector"&&from!="serverside.scalar"&&from!="clientside.scalar")
   {
-  message("            FAILED: <from> must be specified as one of the following - 'serverside.vector',
-        'serverside.scalar', 'clientside.scalar'\n\n")
-  return('Please respecify')
+  .abortInvalidChoice("from", c("serverside.vector", "serverside.scalar", "clientside.scalar"))
   }
 
   if(from=="serverside.vector"||from=="serverside.scalar"){
diff --git a/R/ds.matrixDet.R b/R/ds.matrixDet.R
index 1eb61bd35..da7bc604f 100644
--- a/R/ds.matrixDet.R
+++ b/R/ds.matrixDet.R
@@ -84,9 +84,7 @@ ds.matrixDet<-function(M1=NULL, newobj=NULL, logarithm=FALSE, datasources=NULL){
   datasources <- .resolveDatasources(datasources)
 
   # check if user has provided the name of matrix representing M1
-  if(is.null(M1)){
-    return("Error: Please provide the name of the matrix representing M1")
-  }
+  .checkArgProvided(M1, "the name of the matrix that represents M1")
 
   # if no value or invalid value specified for logarithm, then specify a default
   if(is.null(logarithm)){
diff --git a/R/ds.matrixDet.report.R b/R/ds.matrixDet.report.R
index 963a10f7c..0bc18729b 100644
--- a/R/ds.matrixDet.report.R
+++ b/R/ds.matrixDet.report.R
@@ -80,9 +80,7 @@ ds.matrixDet.report<-function(M1=NULL, logarithm=FALSE, datasources=NULL){
   datasources <- .resolveDatasources(datasources)
 
   # check if user has provided the name of matrix representing M1
-  if(is.null(M1)){
-    return("Error: Please provide the name of the matrix representing M1")
-  }
+  .checkArgProvided(M1, "the name of the matrix that represents M1")
 
   # if no value or invalid value specified for logarithm, then specify a default
   if(is.null(logarithm))
diff --git a/R/ds.matrixDiag.R b/R/ds.matrixDiag.R
index 8808ace42..a53ea007a 100644
--- a/R/ds.matrixDiag.R
+++ b/R/ds.matrixDiag.R
@@ -178,9 +178,7 @@ ds.matrixDiag<-function(x1=NULL, aim=NULL, nrows.scalar=NULL, newobj=NULL, datas
   datasources <- .resolveDatasources(datasources)
 
   # check if a value has been provided for x1
-  if(is.null(x1)){
-    return("Error: x1 must have a value which is a character string, a numeric vector or a scalar")
-  }
+  .checkArgProvided(x1, "a character string, numeric vector or scalar")
 
   # if no value spcified for output object, then specify a default
   newobj <- .resolveNewobjName(newobj, "matrixdiag.newobj")
@@ -190,10 +188,7 @@ ds.matrixDiag<-function(x1=NULL, aim=NULL, nrows.scalar=NULL, newobj=NULL, datas
   if(aim!="serverside.vector.2.matrix"&&aim!="serverside.scalar.2.matrix"&&aim!="serverside.matrix.2.vector"&&
       aim!="clientside.vector.2.matrix"&&aim!="clientside.scalar.2.matrix")
   {
-  message("            FAILED: aim must be specified as one of the following - 'serverside.vector.2.matrix',
-        'serverside.scalar.2.matrix', 'serverside.matrix.2.vector',
-        'clientside.vector.2.matrix', 'clientside.scalar.2.matrix'\n\n")
-  return('Please respecify')
+  .abortInvalidChoice("aim", c("serverside.vector.2.matrix", "serverside.scalar.2.matrix", "serverside.matrix.2.vector", "clientside.vector.2.matrix", "clientside.scalar.2.matrix"))
   }
 
   if(aim=="serverside.vector.2.matrix"||aim=="serverside.scalar.2.matrix"||aim=="serverside.matrix.2.vector")
diff --git a/R/ds.matrixDimnames.R b/R/ds.matrixDimnames.R
index 8d404de95..88e0864a0 100644
--- a/R/ds.matrixDimnames.R
+++ b/R/ds.matrixDimnames.R
@@ -86,9 +86,7 @@ ds.matrixDimnames<-function(M1=NULL, dimnames=NULL, newobj=NULL, datasources=NUL
   datasources <- .resolveDatasources(datasources)
 
   # check if user has provided the name of matrix representing M1
-  if(is.null(M1)){
-    return("Error: Please provide the name of the matrix representing M1")
-  }
+  .checkArgProvided(M1, "the name of the matrix that represents M1")
 
   # if no value specified for output object, then specify a default
   newobj <- .resolveNewobjName(newobj, "matrixdimnames.newobj")
diff --git a/R/ds.matrixInvert.R b/R/ds.matrixInvert.R
index 3e74c2e11..7c81f02c2 100644
--- a/R/ds.matrixInvert.R
+++ b/R/ds.matrixInvert.R
@@ -82,9 +82,7 @@ ds.matrixInvert<-function(M1=NULL, newobj=NULL, datasources=NULL){
   datasources <- .resolveDatasources(datasources)
 
   # check if user has provided the name of matrix representing M1
-  if(is.null(M1)){
-    return("Error: Please provide the name of the matrix representing M1")
-  }
+  .checkArgProvided(M1, "the name of the matrix that represents M1")
 
   # if no value specified for output object, then specify a default
   newobj <- .resolveNewobjName(newobj, "matrixinvert.newobj")
diff --git a/R/ds.matrixMult.R b/R/ds.matrixMult.R
index 7a4c7dd53..cb7c808d8 100644
--- a/R/ds.matrixMult.R
+++ b/R/ds.matrixMult.R
@@ -97,14 +97,10 @@ ds.matrixMult<-function(M1=NULL, M2=NULL, newobj=NULL, datasources=NULL){
   datasources <- .resolveDatasources(datasources)
 
   # check if user has provided the name of matrix representing M1
-  if(is.null(M1)){
-    return("Error: Please provide the name of the matrix representing M1")
-  }
+  .checkArgProvided(M1, "the name of the matrix that represents M1")
 
     # check if user has provided the name of matrix representing M2
-  if(is.null(M2)){
-    return("Error: Please provide the name of the matrix representing M2")
-  }
+  .checkArgProvided(M2, "the name of the matrix that represents M2")
 
 
 
diff --git a/R/ds.matrixTranspose.R b/R/ds.matrixTranspose.R
index 1f8d66c23..a7dd8347c 100644
--- a/R/ds.matrixTranspose.R
+++ b/R/ds.matrixTranspose.R
@@ -85,9 +85,7 @@ ds.matrixTranspose<-function(M1=NULL, newobj=NULL, datasources=NULL){
   datasources <- .resolveDatasources(datasources)
 
   # check if user has provided the name of matrix representing M1
-  if(is.null(M1)){
-    return("Error: Please provide the name of the matrix representing M1")
-  }
+  .checkArgProvided(M1, "the name of the matrix that represents M1")
 
   # if no value spcified for output object, then specify a default
   newobj <- .resolveNewobjName(newobj, "matrixtranspose.newobj")
diff --git a/R/ds.mdPattern.R b/R/ds.mdPattern.R
index 8ab9f5978..4418641b5 100644
--- a/R/ds.mdPattern.R
+++ b/R/ds.mdPattern.R
@@ -117,9 +117,7 @@ ds.mdPattern <- function(x = NULL, type = 'split', datasources = NULL, classCons
 
   datasources <- .resolveDatasources(datasources)
 
-  if(is.null(x)){
-    stop("Please provide the name of a data frame or matrix!", call.=FALSE)
-  }
+  .checkArgProvided(x, "the name of a data.frame or matrix")
 
   # Get study names
   study_names <- names(datasources)
@@ -208,7 +206,7 @@ ds.mdPattern <- function(x = NULL, type = 'split', datasources = NULL, classCons
     ))
 
   } else {
-    stop("Argument 'type' must be either 'split' or 'combine'", call.=FALSE)
+    .abortInvalidChoice("type", c("split", "combine"))
   }
 }
 
diff --git a/R/ds.mean.R b/R/ds.mean.R
index b69450f5c..a83c8e733 100644
--- a/R/ds.mean.R
+++ b/R/ds.mean.R
@@ -99,9 +99,7 @@ ds.mean <- function(x=NULL, type='split', save.mean.Nvalid=FALSE, datasources=NU
 
   datasources <- .resolveDatasources(datasources)
   
-  if(is.null(x)){
-    stop("Please provide the name of the input object!", call.=FALSE)
-  }
+  .checkArgProvided(x, "the name of the input object")
 
 ###################################################################################################
 #MODULE: EXTEND "type" argument to include "both" and enable valid alisases                     #
@@ -109,7 +107,7 @@ if(type == 'combine' | type == 'combined' | type == 'combines' | type == 'c') ty
 if(type == 'split' | type == 'splits' | type == 's') type <- 'split'                              #
 if(type == 'both' | type == 'b' ) type <- 'both'                                                  #
 if(type != 'combine' & type != 'split' & type != 'both'){                                        #
-  stop('Function argument "type" has to be either "both", "combine" or "split"', call.=FALSE)     #
+  .abortInvalidChoice("type", c("both", "combine", "split"))     #
 }  
 
   cally <- call("meanDS", x)
diff --git a/R/ds.meanSdGp.R b/R/ds.meanSdGp.R
index e5cce2731..07ea62795 100644
--- a/R/ds.meanSdGp.R
+++ b/R/ds.meanSdGp.R
@@ -105,13 +105,9 @@ ds.meanSdGp <- function(x=NULL, y=NULL, type='both', datasources=NULL, classCons
 
   datasources <- .resolveDatasources(datasources)
 
-  if(is.null(x)){
-    stop("Please provide the name of the input vector!", call.=FALSE)
-  }
+  .checkArgProvided(x, "the name of the input vector")
 
-  if(is.null(y)){
-    stop("Please provide the name of the input vector!", call.=FALSE)
-  }
+  .checkArgProvided(y, "the name of the input vector")
 
   # names of the studies
   stdnames <- names(datasources)
@@ -142,8 +138,7 @@ ds.meanSdGp <- function(x=NULL, y=NULL, type='both', datasources=NULL, classCons
   }
 
   if(all.tables.valid<1){
-    warning.message<-"At least 1 cell count is 1-nfilter, please regroup"
-    return(warning.message)
+    cli_abort(c("At least one cell count is below {.code nfilter.tab}.", "i" = "Regroup the data and try again."))
   }
 
   if(all.tables.valid==1){
diff --git a/R/ds.merge.R b/R/ds.merge.R
index 95695b6ec..3495e1471 100644
--- a/R/ds.merge.R
+++ b/R/ds.merge.R
@@ -117,31 +117,21 @@ ds.merge <- function(x.name=NULL,y.name=NULL, by.x.names=NULL, by.y.names=NULL,a
   datasources <- .resolveDatasources(datasources)
 
   # dataframe names
-  if(is.null(x.name)){
-    stop("Please provide the name (eg 'name1') of first dataframe to be merged (called x) ", call.=FALSE)
-  }
+  .checkArgProvided(x.name, "the name of the first data.frame to merge")
 
-  if(is.null(y.name)){
-    stop("Please provide the name (eg 'name2') of second dataframe to be merged (called y) ", call.=FALSE)
-  }
+  .checkArgProvided(y.name, "the name of the second data.frame to merge")
 
   # names of columns to merge on (may be more than one)
-  if(is.null(by.x.names)){
-    stop("Please provide the names of columns in x dataframe on which to merge (eg c('id', 'time'))", call.=FALSE)
-	}
+  .checkArgProvided(by.x.names, "the names of the columns in x to merge on")
 
-  if(is.null(by.y.names)){
-    stop("Please provide the names of columns in y dataframe on which to merge (eg c('id', 'time'))", call.=FALSE)
-	}
+  .checkArgProvided(by.y.names, "the names of the columns in y to merge on")
 
 	# make transmittable via parser
   by.x.names.transmit <- paste(by.x.names, collapse=",")
   by.y.names.transmit <- paste(by.y.names, collapse=",")
 
   # suffixes
-  if(is.null(suffixes)){
-    stop("Please provide the suffixes to append to disambiguate duplicate column names (default = c('.x','.y'))", call.=FALSE)
-  }
+  .checkArgProvided(suffixes, "the suffixes that separate duplicate column names")
   
 	# make transmittable via parser
   suffixes.transmit <- paste(suffixes, collapse=",")
diff --git a/R/ds.metadata.R b/R/ds.metadata.R
index c3399bcca..96846d41c 100644
--- a/R/ds.metadata.R
+++ b/R/ds.metadata.R
@@ -54,9 +54,7 @@ ds.metadata = function(x=NULL, datasources=NULL)
 
     #####################################################################################
     #MODULE 3: SET UP KEY VARIABLES ALLOWING FOR DIFFERENT INPUT FORMATS                #
-    if (is.null(x)){                                                                    #
-        stop("Please provide the name of the object!", call.=FALSE)                     #
-    }                                                                                   #
+    .checkArgProvided(x, "the name of an object")                                       #
     #####################################################################################
 
     #####################################################################################
diff --git a/R/ds.mice.R b/R/ds.mice.R
index 6b2ae977f..795a1a30e 100644
--- a/R/ds.mice.R
+++ b/R/ds.mice.R
@@ -52,9 +52,7 @@ ds.mice <- function(data=NULL, m=5, maxit=5, method=NULL, predictorMatrix=NULL,
   datasources <- .resolveDatasources(datasources)
 
   # verify that 'data' was set
-  if(is.null(data)){
-    stop("Please provide the name of the dataframe or matrix that contains the incomplete data!", call.=FALSE)
-  }
+  .checkArgProvided(data, "the name of the data.frame or matrix that holds the incomplete data")
 
   if(!is.null(method)){
     method <- paste0(as.character(method), collapse=",")
diff --git a/R/ds.names.R b/R/ds.names.R
index 8849c1e6a..6d40a034d 100644
--- a/R/ds.names.R
+++ b/R/ds.names.R
@@ -71,9 +71,7 @@ ds.names <- function(xname=NULL, datasources=NULL){
 
   datasources <- .resolveDatasources(datasources)
 
-  if(is.null(xname)){
-    stop("Please provide the name of the input list!", call.=FALSE)
-  }
+  .checkArgProvided(xname, "the name of the input list")
 
   calltext <- call("namesDS", xname)
   output <- DSI::datashield.aggregate(datasources, calltext)
diff --git a/R/ds.numNA.R b/R/ds.numNA.R
index b94840f32..9b1eceeae 100644
--- a/R/ds.numNA.R
+++ b/R/ds.numNA.R
@@ -58,9 +58,7 @@ ds.numNA <- function(x=NULL, datasources=NULL, classConsistencyCheck=TRUE){
 
   datasources <- .resolveDatasources(datasources)
 
-  if(is.null(x)){
-    stop("Please provide the name of a vector!", call.=FALSE)
-  }
+  .checkArgProvided(x, "the name of a vector")
 
   cally <- call("numNaDS", x)
   results <- DSI::datashield.aggregate(datasources, cally)
diff --git a/R/ds.qlspline.R b/R/ds.qlspline.R
index e3900a98e..9240a7f3e 100644
--- a/R/ds.qlspline.R
+++ b/R/ds.qlspline.R
@@ -35,13 +35,9 @@ ds.qlspline <- function(x, q, na.rm = TRUE, marginal = FALSE, names = NULL, newo
   
   datasources <- .resolveDatasources(datasources)
   
-  if(is.null(x)){
-    stop("Please provide the name of the input variable x!", call.=FALSE)
-  }
+  .checkArgProvided(x, "the name of the input variable")
   
-  if(is.null(q)){
-    stop("Argument 'q' is missing, with no default!", call.=FALSE)
-  }
+  .checkArgProvided(q, "a number of quantiles")
   
   # create a name by default if user did not provide a name for the new variable
   newobj <- .resolveNewobjName(newobj, "qlspline.newobj")
diff --git a/R/ds.quantileMean.R b/R/ds.quantileMean.R
index 29dd9373c..2702c8879 100644
--- a/R/ds.quantileMean.R
+++ b/R/ds.quantileMean.R
@@ -71,12 +71,10 @@ ds.quantileMean <- function(x=NULL, type='combine', datasources=NULL, classConsi
 
   datasources <- .resolveDatasources(datasources)
 
-  if(is.null(x)){
-    stop("Please provide the name of the input vector!", call.=FALSE)
-  }
+  .checkArgProvided(x, "the name of the input vector")
 
   if (! all(type %in% c("combine", "split"))) {
-    stop('Function argument "type" has to be either "combine" or "split"', call.=FALSE)
+    .abortInvalidChoice("type", c("combine", "split"))
   }
 
   # get the server function that produces the quantiles
@@ -116,7 +114,7 @@ ds.quantileMean <- function(x=NULL, type='combine', datasources=NULL, classConsi
     if(type=="split"){
       return(quants)
     }else{
-      stop('Function argument "type" has to be either "combine" or "split"', call.=FALSE)
+      .abortInvalidChoice("type", c("combine", "split"))
     }
   }
 }
diff --git a/R/ds.rBinom.R b/R/ds.rBinom.R
index 339bbc574..c1b41eff1 100644
--- a/R/ds.rBinom.R
+++ b/R/ds.rBinom.R
@@ -113,22 +113,7 @@ ds.rBinom<-function(samp.size=1,size=0,prob=1, newobj=NULL, seed.as.integer=NULL
 
 ########################
 #TEST SEED PRIMING VALUE
-seed.valid<-0
-
-if(is.null(seed.as.integer)){
-seed.as.text<-"NULL"
-seed.valid<-1
-}
-
-if(is.numeric(seed.as.integer)){
-seed.as.text<-as.character(seed.as.integer)
-seed.valid<-1
-}
-
-if(seed.valid==0){
-mess1<-("ERROR failed: seed.as.integer must be set as an integer [numeric] or left NULL")
-return(mess1)
-}
+seed.as.text <- .seedAsText(seed.as.integer)
 
 ###################################################################################
 #samp.size is either a numeric scalar or a numeric vector set
@@ -140,16 +125,7 @@ return(mess1)
 #Such serverside vectors must be named in inverted commas. These get
 #stripped off when the vector name is passed to the serverside.
 
-arguments.valid<-1
-
-if(is.null(samp.size)||is.null(size)||is.null(prob)||is.null(newobj)){
-arguments.valid<-0
-}
-
-if(!arguments.valid){
-mess2<-("ERROR: appropriate values must be set for samp.size, size, prob, and newobj name")
-return(mess2)
-}
+.checkArgsSet(samp.size = samp.size, size = size, prob = prob, newobj = newobj)
 
 numsources<-length(datasources)
 size<-.expandToStudies(size, "size", numsources)
@@ -163,8 +139,7 @@ if(is.numeric(size)){
 }
 
 if(!size.valid){
-mess3<-("ERROR: size must be > 0")
-return(mess3)
+cli_abort("{.arg size} must be greater than 0.")
 }
 
 prob.valid<-1
@@ -175,8 +150,7 @@ if(is.numeric(prob)){
 }
 
 if(!prob.valid){
-mess4<-("ERROR: prob must lie in range 0 < prob < 1")
-return(mess4)
+cli_abort("{.arg prob} must be between 0 and 1.")
 }
 
 
diff --git a/R/ds.rNorm.R b/R/ds.rNorm.R
index 46a3d7b8f..0aeec29af 100644
--- a/R/ds.rNorm.R
+++ b/R/ds.rNorm.R
@@ -124,22 +124,7 @@ ds.rNorm<-function(samp.size=1,mean=0,sd=1, newobj="newObject", seed.as.integer=
 
 ########################
 #TEST SEED PRIMING VALUE
-seed.valid<-0
-
-if(is.null(seed.as.integer)){
-seed.as.text<-"NULL"
-seed.valid<-1
-}
-
-if(is.numeric(seed.as.integer)){
-seed.as.text<-as.character(seed.as.integer)
-seed.valid<-1
-}
-
-if(seed.valid==0){
-mess1<-("ERROR failed: seed.as.integer must be set as an integer [numeric] or left NULL")
-return(mess1)
-}
+seed.as.text <- .seedAsText(seed.as.integer)
 
 ###################################################################################
 #samp.size is either a numeric scalar or a numeric vector set
@@ -151,16 +136,7 @@ return(mess1)
 #Such serverside vectors must be named in inverted commas. These get
 #stripped off when the vector name is passed to the serverside.
 
-arguments.valid<-1
-
-if(is.null(samp.size)||is.null(mean)||is.null(sd)||is.null(newobj)){
-arguments.valid<-0
-}
-
-if(!arguments.valid){
-mess2<-("ERROR: appropriate values must be set for samp.size, mean, sd, and newobj name")
-return(mess2)
-}
+.checkArgsSet(samp.size = samp.size, mean = mean, sd = sd, newobj = newobj)
 
 numsources<-length(datasources)
 mean<-.expandToStudies(mean, "mean", numsources)
@@ -175,8 +151,7 @@ if(is.numeric(sd)){
 }
 
 if(!sd.valid){
-mess3<-("ERROR: sd must be > 0")
-return(mess3)
+cli_abort("{.arg sd} must be greater than 0.")
 }
 
 decimal.places.valid<-1
@@ -185,8 +160,7 @@ decimal.places.valid<-0
 }
 
 if(!decimal.places.valid){
-mess4<-("ERROR: force.output.to.k.decimal.places must be an integer in range 0-9")
-return(mess4)
+cli_abort("{.arg force.output.to.k.decimal.places} must be an integer between 0 and 9.")
 }
 ###################################################################################
 
diff --git a/R/ds.rPois.R b/R/ds.rPois.R
index 4840eaaea..1b85d82c3 100644
--- a/R/ds.rPois.R
+++ b/R/ds.rPois.R
@@ -106,22 +106,7 @@ ds.rPois<-function(samp.size=1,lambda=1, newobj="newObject", seed.as.integer=NUL
 
 ########################
 #TEST SEED PRIMING VALUE
-seed.valid<-0
-
-if(is.null(seed.as.integer)){
-seed.as.text<-"NULL"
-seed.valid<-1
-}
-
-if(is.numeric(seed.as.integer)){
-seed.as.text<-as.character(seed.as.integer)
-seed.valid<-1
-}
-
-if(seed.valid==0){
-mess1<-("ERROR failed: seed.as.integer must be set as an integer [numeric] or left NULL")
-return(mess1)
-}
+seed.as.text <- .seedAsText(seed.as.integer)
 
 ###################################################################################
 #samp.size is either a numeric scalar or a numeric vector set
@@ -133,16 +118,7 @@ return(mess1)
 #Such serverside vectors must be named in inverted commas. These get
 #stripped off when the vector name is passed to the serverside.
 
-arguments.valid<-1
-
-if(is.null(samp.size)||is.null(lambda)||is.null(newobj)){
-arguments.valid<-0
-}
-
-if(!arguments.valid){
-mess2<-("ERROR: appropriate values must be set for samp.size, lambda, and newobj name")
-return(mess2)
-}
+.checkArgsSet(samp.size = samp.size, lambda = lambda, newobj = newobj)
 
 numsources<-length(datasources)
 lambda<-.expandToStudies(lambda, "lambda", numsources)
@@ -155,8 +131,7 @@ if(is.numeric(lambda)){
 }
 
 if(!lambda.valid){
-mess3<-("ERROR: lambda must be > 0")
-return(mess3)
+cli_abort("{.arg lambda} must be greater than 0.")
 }
 ###################################################################################
 
diff --git a/R/ds.rUnif.R b/R/ds.rUnif.R
index 71fe5bec3..3f047a2eb 100644
--- a/R/ds.rUnif.R
+++ b/R/ds.rUnif.R
@@ -132,22 +132,7 @@ ds.rUnif<-function(samp.size=1,min=0,max=1, newobj="newObject", seed.as.integer=
 
 ########################
 #TEST SEED PRIMING VALUE
-seed.valid<-0
-
-if(is.null(seed.as.integer)){
-seed.as.text<-"NULL"
-seed.valid<-1
-}
-
-if(is.numeric(seed.as.integer)){
-seed.as.text<-as.character(seed.as.integer)
-seed.valid<-1
-}
-
-if(seed.valid==0){
-mess1<-("ERROR failed: seed.as.integer must be set as an integer [numeric] or left NULL")
-return(mess1)
-}
+seed.as.text <- .seedAsText(seed.as.integer)
 
 ###################################################################################
 #samp.size is either a numeric scalar or a numeric vector set
@@ -159,17 +144,7 @@ return(mess1)
 #Such serverside vectors must be named in inverted commas. These get
 #stripped off when the vector name is passed to the serverside.
 
-arguments.valid<-1
-
-if(is.null(samp.size)||is.null(min)||is.null(max)||is.null(newobj)){
-arguments.valid<-0
-}
-
-
-if(!arguments.valid){
-mess2<-("ERROR: appropriate values must be set for samp.size, min, max, and newobj name")
-return(mess2)
-}
+.checkArgsSet(samp.size = samp.size, min = min, max = max, newobj = newobj)
 
 numsources<-length(datasources)
 min<-.expandToStudies(min, "min", numsources)
@@ -187,8 +162,7 @@ if(is.numeric(min) && is.numeric(max)){
 }
 
 if(!minmax.valid){
-mess3<-("ERROR: max must be greater than min")
-return(mess3)
+cli_abort("{.arg max} must be greater than {.arg min}.")
 }
 
 decimal.places.valid<-1
@@ -197,8 +171,7 @@ decimal.places.valid<-0
 }
 
 if(!decimal.places.valid){
-mess4<-("ERROR: force.output.to.k.decimal.places must be an integer in range 0-9")
-return(mess4)
+cli_abort("{.arg force.output.to.k.decimal.places} must be an integer between 0 and 9.")
 }
 
 
diff --git a/R/ds.rbind.R b/R/ds.rbind.R
index 90ee2a89f..af5086bde 100644
--- a/R/ds.rbind.R
+++ b/R/ds.rbind.R
@@ -85,21 +85,14 @@ ds.rbind<-function(x=NULL, DataSHIELD.checks=FALSE, force.colnames=NULL, newobj=
 
   datasources <- .resolveDatasources(datasources)
 
-  if(is.null(x)){
-    stop("Please provide a vector of character strings holding the name of the input elements!", call.=FALSE)
-  }
+  .checkArgProvided(x, "a vector of the names of the input elements")
 
 
   if(DataSHIELD.checks){
 
     # call the internal function that checks the input object(s) is(are) of the same legal class in all studies.
     if(classConsistencyCheck){
-    for(i in 1:length(x)){
-      typ <- checkClass(datasources, x[i])
-      if(!('data.frame' %in% typ) & !('matrix' %in% typ) & !('factor' %in% typ) & !('character' %in% typ) & !('numeric' %in% typ) & !('integer' %in% typ) & !('logical' %in% typ)){
-        stop(" Only objects of type 'data.frame', 'matrix', 'numeric', 'integer', 'character', 'factor' and 'logical' are allowed.", call.=FALSE)
-      }
-    }
+    .checkObjectClasses(datasources, x)
     }
   }
   
diff --git a/R/ds.reShape.R b/R/ds.reShape.R
index bf7a2e2fd..f19f2930d 100644
--- a/R/ds.reShape.R
+++ b/R/ds.reShape.R
@@ -84,9 +84,7 @@ ds.reShape <- function(data.name=NULL, varying=NULL, v.names=NULL, timevar.name=
 
   datasources <- .resolveDatasources(datasources)
 
-  if(is.null(data.name)){
-    stop("Please provide the name of the list that holds the input vectors!", call.=FALSE)
-  }
+  .checkArgProvided(data.name, "the name of the list that holds the input vectors")
 
   if (!is.character(sep) || (nchar(sep) != 1)){
     stop("'sep' must be a character string", call.=FALSE)
diff --git a/R/ds.recodeValues.R b/R/ds.recodeValues.R
index 7dca9b737..1fb3d5dff 100644
--- a/R/ds.recodeValues.R
+++ b/R/ds.recodeValues.R
@@ -82,9 +82,7 @@ ds.recodeValues <- function(var.name=NULL, values2replace.vector=NULL, new.value
   datasources <- .resolveDatasources(datasources)
 
   # check user has provided the name of the variable to be recoded
-  if(is.null(var.name)){
-    stop("Please provide the name of the variable to be recoded: eg 'xxx'", call.=FALSE)
-  }
+  .checkArgProvided(var.name, "the name of the variable to recode")
 
   # check user has provided the vector specifying the set of values to be replaced
   if(is.null(values2replace.vector)){
diff --git a/R/ds.rep.R b/R/ds.rep.R
index 53ccaa92e..34464bcdd 100644
--- a/R/ds.rep.R
+++ b/R/ds.rep.R
@@ -99,9 +99,7 @@ ds.rep<-function(x1=NULL,  times=NA,  length.out=NA, each=1,
   datasources <- .resolveDatasources(datasources)
 
   # check if a value has been provided for x1
-  if(is.null(x1)){
-    return("Error: x1 must have a value which is a character string, a numeric vector on the clientside or a scalar")
-  }
+  .checkArgProvided(x1, "a character string, a client-side numeric vector or a scalar")
 
   # if no value specified for output object, then specify a default
   newobj <- .resolveNewobjName(newobj, paste0("seq.vect"))
@@ -138,9 +136,7 @@ if(source.each=='s')source.each<-'serverside'
   #Check that source has been specified
   if(source.x1!="serverside"&&source.x1!="clientside")
   {
-  message("            FAILED: if source.x1 is non-null it must be specified as
-  one of the following: 'clientside','serverside','c', or 's'\n\n")
-  return('Please respecify')
+  .abortInvalidChoice("source.x1", c("clientside", "serverside", "c", "s"))
   }
 
   #process appropriately for source
@@ -161,9 +157,7 @@ if(source.each=='s')source.each<-'serverside'
  #Check that source has been specified
   if(source.times!="serverside"&&source.times!="clientside"&&!is.null(source.times))
   {
-  message("            FAILED: if source.times is non-null it must be specified as
-  one of the following: 'clientside','serverside','c', or 's'\n\n")
-  return('Please respecify')
+  .abortInvalidChoice("source.times", c("clientside", "serverside", "c", "s"))
   }
 
 
@@ -195,9 +189,7 @@ if(source.each=='s')source.each<-'serverside'
   #Check that source has been specified
   if(source.length.out!="serverside"&&source.length.out!="clientside"&&!is.null(source.length.out))
   {
-  message("            FAILED: if source.length.out is non-null it must be specified as
-  one of the following: 'clientside','serverside','c', or 's'\n\n")
-  return('Please respecify')
+  .abortInvalidChoice("source.length.out", c("clientside", "serverside", "c", "s"))
   }
 
 
@@ -230,9 +222,7 @@ if(source.each=='s')source.each<-'serverside'
   #Check that source has been specified
   if(source.each!="serverside"&&source.each!="clientside"&&!is.null(source.each))
   {
-  message("            FAILED: if source.each is non-null it must be specified as
-  one of the following: 'clientside','serverside','c', or 's'\n\n")
-  return('Please respecify')
+  .abortInvalidChoice("source.each", c("clientside", "serverside", "c", "s"))
   }
 
 
diff --git a/R/ds.replaceNA.R b/R/ds.replaceNA.R
index 8f41e8984..a502ccc8e 100644
--- a/R/ds.replaceNA.R
+++ b/R/ds.replaceNA.R
@@ -94,17 +94,12 @@ ds.replaceNA <- function(x=NULL, forNA=NULL, newobj=NULL, datasources=NULL){
 
   datasources <- .resolveDatasources(datasources)
 
-  if(is.null(x)){
-    stop("Please provide the name of a vector!", call.=FALSE)
-  }
+  .checkArgProvided(x, "the name of a vector")
 
   # check if replacement values have been provided
-  if(is.null(forNA)){
-    stop("Please provide a list of replacement values!", call.=FALSE)
-  }else{
-    if(length(forNA) != length(datasources)){
-      stop("'forNA' must be of the same length as the number of datasources/studies!", call.=FALSE)
-    }
+  .checkArgProvided(forNA, "a list of replacement values")
+  if(length(forNA) != length(datasources)){
+    cli_abort("{.arg forNA} must have one element per study.")
   }
 
   for(i in 1:length(datasources)){
diff --git a/R/ds.rm.R b/R/ds.rm.R
index 90b308017..e923aec30 100644
--- a/R/ds.rm.R
+++ b/R/ds.rm.R
@@ -71,9 +71,7 @@ ds.rm<-function(x.names=NULL, datasources=NULL){
     
     datasources <- .resolveDatasources(datasources)
     
-    if (is.null(x.names)) {
-        stop("Please provide the names of the objects to be deleted (eg 'object.name') as the x.names argument", call.=FALSE)
-    }
+    .checkArgProvided(x.names, "the names of the objects to delete")
     
     #make transmittable via parser
     x.names.transmit <- paste(x.names,collapse=",")
diff --git a/R/ds.rowColCalc.R b/R/ds.rowColCalc.R
index 6a963650f..629e1575a 100644
--- a/R/ds.rowColCalc.R
+++ b/R/ds.rowColCalc.R
@@ -70,9 +70,7 @@ ds.rowColCalc <- function(x=NULL, operation=NULL, newobj=NULL, datasources=NULL)
 
   datasources <- .resolveDatasources(datasources)
 
-  if(is.null(x)){
-    stop("Please provide the name of a data.frame or matrix!", call.=FALSE)
-  }
+  .checkArgProvided(x, "the name of a data.frame or matrix")
 
   ops <- c("rowSums","colSums","rowMeans","colMeans")
   if(is.null(operation)){
@@ -81,7 +79,7 @@ ds.rowColCalc <- function(x=NULL, operation=NULL, newobj=NULL, datasources=NULL)
     stop("'operation' = NULL. Please set it to 'rowSums', 'colSums', 'rowMeans' or 'colMeans'", call.=FALSE)
   }else{
     if(!any(operation %in% ops)){
-      stop("'operation' must be set to: 'rowSums', 'colSums', 'rowMeans' or 'colMeans'")
+      .abortInvalidChoice("operation", ops)
     }
   }
 
diff --git a/R/ds.sample.R b/R/ds.sample.R
index 80c92e34f..422d9e264 100644
--- a/R/ds.sample.R
+++ b/R/ds.sample.R
@@ -133,15 +133,13 @@ ds.sample<-function(x=NULL,  size=NULL, seed.as.integer=NULL, replace=FALSE, pro
   datasources <- .resolveDatasources(datasources)
 
   # check if a value has been provided for x
-  if(is.null(x)){
-    return("Error: x must denote a character string naming the serverside object to be sampled or an integer N denoting permute 1:N")
-  }
+  .checkArgProvided(x, "a character string that names a server-side object, or an integer N to permute 1:N")
 
  # check if a valid value has been provided for size if x denotes a vector,
  # matrix or data.frame on the serverside
  
   if(is.character(x)&&is.null(size)){
-    return("Error: size must have a value which is an integer denoting how many records to be sampled")
+    cli_abort("{.arg size} must be an integer that sets how many records to sample.")
   }
 
   # if no value specified for output object, then specify a default
@@ -149,22 +147,7 @@ ds.sample<-function(x=NULL,  size=NULL, seed.as.integer=NULL, replace=FALSE, pro
 
 ########################
 #TEST SEED PRIMING VALUE
-seed.valid<-0
-
-if(is.null(seed.as.integer)){
-seed.as.text<-"NULL"
-seed.valid<-1
-}
-
-if(is.numeric(seed.as.integer)){
-seed.as.text<-as.character(seed.as.integer)
-seed.valid<-1
-}
-
-if(seed.valid==0){
-mess1<-("ERROR failed: seed.as.integer must be set as an integer [numeric] or left NULL")
-return(mess1)
-}
+seed.as.text <- .seedAsText(seed.as.integer)
 
 #############################################################
 #SET SEED IN EACH STUDY AS IN PSEUDORANDOM NUMBER GENERATORS
diff --git a/R/ds.scatterPlot.R b/R/ds.scatterPlot.R
index 4ee76e92c..11a0a7248 100644
--- a/R/ds.scatterPlot.R
+++ b/R/ds.scatterPlot.R
@@ -131,13 +131,9 @@
 #'
 ds.scatterPlot <- function(x=NULL, y=NULL, method='deterministic', k=3, noise=0.25, type="split", return.coords=FALSE, datasources=NULL, classConsistencyCheck=FALSE){
 
-  if(is.null(x)){
-    stop("Please provide the name of the x-variable", call.=FALSE)
-  }
+  .checkArgProvided(x, "the name of the x variable")
 
-  if(is.null(y)){
-    stop("Please provide the name of the y-variable", call.=FALSE)
-  }
+  .checkArgProvided(y, "the name of the y variable")
 
   datasources <- .resolveDatasources(datasources)
 
@@ -214,7 +210,7 @@ ds.scatterPlot <- function(x=NULL, y=NULL, method='deterministic', k=3, noise=0.
           return(message=return.message)
         }  
     }else{
-      stop('Function argument "type" has to be either "combine" or "split"')
+      .abortInvalidChoice("type", c("combine", "split"))
     }
   }
 }
diff --git a/R/ds.seq.R b/R/ds.seq.R
index ee81f29d4..e6a0cad52 100644
--- a/R/ds.seq.R
+++ b/R/ds.seq.R
@@ -127,7 +127,7 @@ ds.seq<-function(FROM.value.char = "1", BY.value.char = "1", TO.value.char=NULL,
 		if(!is.numeric(eval(parse(text=FROM.value.char))))FROM.valid<-0
 	}
 	if(!FROM.valid){
-  return("Error: If FROM.value.char is non.NULL, it must be a real number in inverted commas eg '-3.7' or '0'")
+  cli_abort(c("{.arg FROM.value.char} must be a real number in inverted commas.", "i" = "For example, {.val -3.7} or {.val 0}."))
 	}
 
 ###TO.value.char
@@ -138,7 +138,7 @@ ds.seq<-function(FROM.value.char = "1", BY.value.char = "1", TO.value.char=NULL,
 		if(!is.numeric(eval(parse(text=TO.value.char))))TO.valid<-0
 	}
 	if(!TO.valid){
-  return("Error: If TO.value.char is non.NULL, it must be a real number in inverted commas eg '-3.7' or '0'")
+  cli_abort(c("{.arg TO.value.char} must be a real number in inverted commas.", "i" = "For example, {.val -3.7} or {.val 0}."))
 	}
 
 ###BY.value.char
@@ -149,7 +149,7 @@ ds.seq<-function(FROM.value.char = "1", BY.value.char = "1", TO.value.char=NULL,
 		if(!is.numeric(eval(parse(text=BY.value.char))))BY.valid<-0
 	}
 	if(!BY.valid){
-  return("Error: If FROM.value.char is non.NULL, it must be a real number in inverted commas eg '5' or '-98.7321'")
+  cli_abort(c("{.arg BY.value.char} must be a real number in inverted commas.", "i" = "For example, {.val 5} or {.val -98.7321}."))
 	}
 
 ###LENGTH.OUT.value.char
@@ -160,19 +160,19 @@ ds.seq<-function(FROM.value.char = "1", BY.value.char = "1", TO.value.char=NULL,
 		if(!is.numeric(eval(parse(text=LENGTH.OUT.value.char))))LENGTH.OUT.valid<-0
 	}
 	if(!LENGTH.OUT.valid){
-  return("Error: If LENGTH.OUT.value.char is non.NULL, it must be an integer in inverted commas eg '87187'")
+  cli_abort(c("{.arg LENGTH.OUT.value.char} must be an integer in inverted commas.", "i" = "For example, {.val 87187}."))
 	}
 
 
 ###ALONG.WITH.name
   # check if user has correctly provided the name of a column to hold ALONG.WITH.name
   if(!(is.null(ALONG.WITH.name) || is.character(ALONG.WITH.name))){
-    return("Error: If ALONG.WITH.name is non.NULL, it must specify the name of a serverside vector in inverted commas")
+    cli_abort("{.arg ALONG.WITH.name} must be the name of a server-side vector in inverted commas.")
 	}
 
 ###Either LENGTH.OUT.value.char or ALONG.WITH.name must be non-NULL
 if(is.null(TO.value.char)&&is.null(LENGTH.OUT.value.char)&&is.null(ALONG.WITH.name)){
-    return("Error: Either TO.value.char or LENGTH.OUT.value.char or ALONG.WITH.name must be non-NULL, they cannot both be NULL")
+    cli_abort("One of {.arg TO.value.char}, {.arg LENGTH.OUT.value.char} or {.arg ALONG.WITH.name} must be set.")
 	}
 
 
diff --git a/R/ds.setSeed.R b/R/ds.setSeed.R
index 2768c540e..e14b275fa 100644
--- a/R/ds.setSeed.R
+++ b/R/ds.setSeed.R
@@ -90,23 +90,7 @@ ds.setSeed<-function(seed.as.integer=NULL,datasources=NULL){
   datasources <- .resolveDatasources(datasources)
 
 
-seed.valid<-0
-
-if(is.null(seed.as.integer)){
-seed.as.text<-"NULL"
-seed.valid<-1
-}
-
-if(is.numeric(seed.as.integer)){
-seed.as.text<-as.character(seed.as.integer)
-seed.valid<-1
-}
-
-
-if(seed.valid==0){
-mess1<-("ERROR terminated: seed.as.integer must be set as an integer [numeric] or as being NULL")
-return(mess1)
-}
+seed.as.text <- .seedAsText(seed.as.integer)
 
   ssDS.obj <- datashield.aggregate(datasources, call("setSeedDS", seedtext=seed.as.text))
 
diff --git a/R/ds.skewness.R b/R/ds.skewness.R
index 4f4525718..324f05109 100644
--- a/R/ds.skewness.R
+++ b/R/ds.skewness.R
@@ -83,9 +83,7 @@ ds.skewness <- function(x=NULL, method=1, type='both', datasources=NULL, classCo
 
   datasources <- .resolveDatasources(datasources)
 
-  if(is.null(x)){
-    stop("Please provide the name of the input vector!", call.=FALSE)
-  }
+  .checkArgProvided(x, "the name of the input vector")
   
   if(!all(method %in% c(1,2,3))){
     stop("method must be an integer between 1 and 3", call.=FALSE)
@@ -96,7 +94,7 @@ ds.skewness <- function(x=NULL, method=1, type='both', datasources=NULL, classCo
   if(type == 'split' | type == 'splits' | type == 's') type <- 'split'
   if(type == 'both' | type == 'b' ) type <- 'both'
   if(type != 'combine' & type != 'split' & type != 'both')
-    stop('Function argument "type" has to be either "both", "combine" or "split"', call.=FALSE)
+    .abortInvalidChoice("type", c("both", "combine", "split"))
 
   if (type=='split' | type=='both'){
     calltext.split <- call("skewnessDS1", x, method)
diff --git a/R/ds.sqrt.R b/R/ds.sqrt.R
index 332088f08..376fa212a 100644
--- a/R/ds.sqrt.R
+++ b/R/ds.sqrt.R
@@ -73,9 +73,7 @@ ds.sqrt <- function(x=NULL, newobj=NULL, datasources=NULL){
 
   datasources <- .resolveDatasources(datasources)
 
-  if(is.null(x)){
-    stop("Please provide the name of the input object!", call.=FALSE)
-  }
+  .checkArgProvided(x, "the name of the input object")
 
   newobj <- .resolveNewobjName(newobj, "sqrt.newobj")
 
diff --git a/R/ds.summary.R b/R/ds.summary.R
index 19876a274..d6824a740 100644
--- a/R/ds.summary.R
+++ b/R/ds.summary.R
@@ -69,9 +69,7 @@ ds.summary <- function(x=NULL, datasources=NULL){
 
   datasources <- .resolveDatasources(datasources)
 
-  if(is.null(x)){
-    stop("Please provide the name of the input vector!", call.=FALSE)
-  }
+  .checkArgProvided(x, "the name of the input vector")
 
   # check the type of x to drive client-side dispatch
   typ <- checkClass(datasources, x)
diff --git a/R/ds.table.R b/R/ds.table.R
index 951cf186e..605ba1c8c 100644
--- a/R/ds.table.R
+++ b/R/ds.table.R
@@ -194,24 +194,22 @@ ds.table <- function(rvar=NULL, cvar=NULL, stvar=NULL, report.chisq.tests=FALSE,
   datasources <- .resolveDatasources(datasources)
 
   # check if a value has been provided for rvar
-  if(is.null(rvar)){
-    return("Error: rvar must have a value which is a character string naming the row variable for the table")
-  }
+  .checkArgProvided(rvar, "a character string that names the row variable")
   
   if(!is.null(cvar)&&!is.character(cvar)){
-     return("Error: if cvar is not null, it must have a value which is a character string naming the column variable for the table")
+     cli_abort("{.arg cvar} must be a character string that names the column variable.")
   }
   
   if(!is.null(stvar)&&!is.character(stvar)){
-     return("Error: if stvar is not null, it must have a value which is a character string naming the variable coding separate tables for the table")
+     cli_abort("{.arg stvar} must be a character string that names the variable that codes the separate tables.")
   }
   
   if(useNA!="no" && useNA!="always"){
-     stop("useNA must be either 'no' or 'always'.")
+     .abortInvalidChoice("useNA", c("no", "always"))
 	 }
 
   if(!is.null(force.nfilter)&&!is.character(force.nfilter)){
-     return("Error: if force.nfilter is not null, it must have a value which is a character string specifying an integer for the forced value of the nfilter")
+     cli_abort("{.arg force.nfilter} must be a character string that specifies an integer.")
   }
 
 
@@ -402,14 +400,8 @@ if(num.valid.studies==0)
 {
 	if ((! table.assign) || report.chisq.tests)
 	{
-	    validity.message<-"All studies failed for reasons identified below"
-	    message("\n",validity.message,"\n\n")
-	    for(ns in 1:numsources.orig)
-	    {
-	        message("\nStudy",ns,": ",error.messages[[ns]],"\n")
-	    }
-
-	    return(list(validity.message=validity.message,error.messages=error.messages))
+	    failures <- paste0(names(error.messages), ": ", unlist(error.messages))
+	    cli_abort(c("All studies failed.", "x" = "{failures}"))
 	}
 	else
 	{
@@ -498,8 +490,7 @@ if(numsources>1)
       if(table.dimensions[ns]!=table.dimensions[ns+1])
       {
       all.dims.same<-FALSE
-      return.message<-"Warning: tables in different sources have different numbers of dimensions. Please analyse and combine yourself from study.specific tables above" 
-      return(return.message)   
+      cli_abort(c("Tables in different sources have different numbers of dimensions.", "i" = "Analyse and combine them yourself from the study-specific tables."))
       }
     }
 
@@ -715,9 +706,7 @@ for(oo in 1:length(table.current.study[,1]))
    
   if(d1.a!=d1||d2.a!=d2||d3.a!=d3)
   {
-  return.message=  "Dimensions of tables not behaving sensibly across studies.Please check the data in each study and calculate counts and percentages, yourself, using the counts from the individual studies"
-  message(return.message)
-  return(return.message) 
+  cli_abort(c("Table dimensions differ across studies.", "i" = "Check the data in each study and calculate counts and percentages yourself from the counts in each study."))
   }
   
   #dimension markers match so allocate count to correct cell
@@ -936,9 +925,7 @@ for(oo in 1:length(table.current.study[,1]))
    
   if(d1.a!=d1||d2.a!=d2)
   {
-  return.message=  "Dimensions of tables not behaving sensibly across studies.Please check the data in each study and calculate counts and percentages, yourself, using the counts from the individual studies"
-  message(return.message)
-  return(return.message) 
+  cli_abort(c("Table dimensions differ across studies.", "i" = "Check the data in each study and calculate counts and percentages yourself from the counts in each study."))
   }
   
   #dimension markers match so allocate count to correct cell
@@ -1130,9 +1117,7 @@ for(oo in 1:length(table.current.study[,1]))
 
   if(d1.a!=d1)
   {
-  return.message=  "Dimensions of tables not behaving sensibly across studies.Please check the data in each study and calculate counts and percentages, yourself, using the counts from the individual studies"
-  message(return.message)
-  return(return.message) 
+  cli_abort(c("Table dimensions differ across studies.", "i" = "Check the data in each study and calculate counts and percentages yourself from the counts in each study."))
   }
   
   #dimension markers match so allocate count to correct cell
diff --git a/R/ds.tapply.R b/R/ds.tapply.R
index bd75001f4..0ca7829ed 100644
--- a/R/ds.tapply.R
+++ b/R/ds.tapply.R
@@ -129,17 +129,12 @@ ds.tapply <- function(X.name=NULL, INDEX.names=NULL, FUN.name=NULL, datasources=
 
   ###X.name
   # check if user has provided the name of the column that holds X.name
-  if(is.null(X.name)){
-    return("Error: Please provide the name of the variable to be summarized, as a character string")
-  }
+  .checkArgProvided(X.name, "the name of the variable to summarise, as a character string")
   
   ###INDEX.names
   # check if user has provided the name of the column(s) that holds INDEX.names
   if(is.null(INDEX.names)){
-    Err.1 <- "Error: Please provide the name of the single factor or"
-    Err.2 <- "the list of factors to index the variable to be summarized."
-    Err.3 <- "In either case the argument must be specified in inverted commas"
-    return(list(Error.message=Err.1, Err.cont2=Err.2, Err.cont3=Err.3))
+    cli_abort("{.arg INDEX.names} must name a single factor or a list of factors, in inverted commas.")
   }
   
   # check if the vector or list of INDEX.names includes up to two names
@@ -156,9 +151,7 @@ ds.tapply <- function(X.name=NULL, INDEX.names=NULL, FUN.name=NULL, datasources=
 
   ###FUN.name
   # check if user has provided a valid summarizing function
-  if(is.null(FUN.name)){
-    return("Error: Please provide a valid summarizing function, as a character string")
-  }
+  .checkArgProvided(FUN.name, "a valid summarising function, as a character string")
 
   # CALL THE PRIMARY SERVER SIDE FUNCTION
   calltext <- call("tapplyDS", X.name, INDEX.names.transmit, FUN.name)
diff --git a/R/ds.tapply.assign.R b/R/ds.tapply.assign.R
index b9fa21ffa..9438b21a9 100644
--- a/R/ds.tapply.assign.R
+++ b/R/ds.tapply.assign.R
@@ -134,17 +134,12 @@ ds.tapply.assign <- function(X.name=NULL, INDEX.names=NULL, FUN.name=NULL, newob
 
   ###X.name
   # check if user has provided the name of the column that holds X.name
-  if(is.null(X.name)){
-    return("Error: Please provide the name of the variable to be summarized, as a character string")
-  }
+  .checkArgProvided(X.name, "the name of the variable to summarise, as a character string")
   
   ###INDEX.names
   # check if user has provided the name of the column(s) that holds INDEX.names
   if(is.null(INDEX.names)){
-    Err.1 <- "Error: Please provide the name of the single factor or"
-    Err.2 <- "the list of factors to index the variable to be summarized."
-    Err.3 <- "In either case the argument must be specified in inverted commas"
-    return(list(Error.message=Err.1, Err.cont2=Err.2, Err.cont3=Err.3))
+    cli_abort("{.arg INDEX.names} must name a single factor or a list of factors, in inverted commas.")
   }
   
   # check if the vector or list of INDEX.names includes up to two names
@@ -161,9 +156,7 @@ ds.tapply.assign <- function(X.name=NULL, INDEX.names=NULL, FUN.name=NULL, newob
   
   ###FUN.name
   # check if user has provided a valid summarizing function
-  if(is.null(FUN.name)){
-    return("Error: Please provide a valid summarizing function, as a character string")
-  }
+  .checkArgProvided(FUN.name, "a valid summarising function, as a character string")
 
     # create a name by default if user did not provide a name for the new tapply object
   newobj <- .resolveNewobjName(newobj, "tapply.assign.newobj")
diff --git a/R/ds.unList.R b/R/ds.unList.R
index c2418cd48..3df4dd01b 100644
--- a/R/ds.unList.R
+++ b/R/ds.unList.R
@@ -72,9 +72,7 @@ ds.unList <- function(x.name=NULL, newobj=NULL, datasources=NULL){
 
   datasources <- .resolveDatasources(datasources)
 
-  if(is.null(x.name)){
-    stop("Please provide the name of the input vector!", call.=FALSE)
-  }
+  .checkArgProvided(x.name, "the name of the input vector")
 
 
   # create a name by default if user did not provide a name for the new variable
diff --git a/R/ds.unique.R b/R/ds.unique.R
index 97dc824a4..4c09b74fd 100644
--- a/R/ds.unique.R
+++ b/R/ds.unique.R
@@ -50,9 +50,7 @@ ds.unique <- function(x.name = NULL, newobj = NULL, datasources = NULL) {
 
     datasources <- .resolveDatasources(datasources)
 
-    if (is.null(x.name)) {
-        stop("x.name=NULL. Please provide the names of the objects to de-duplicated!", call. = FALSE)
-    }
+    .checkArgProvided(x.name, "the names of the objects to de-duplicate")
 
     newobj <- .resolveNewobjName(newobj, "unique.newobj")
 
diff --git a/R/ds.var.R b/R/ds.var.R
index 0256de603..4266f57ef 100644
--- a/R/ds.var.R
+++ b/R/ds.var.R
@@ -77,9 +77,7 @@ ds.var <- function(x=NULL, type='split', datasources=NULL, classConsistencyCheck
 
   datasources <- .resolveDatasources(datasources)
 
-  if(is.null(x)){
-    stop("Please provide the name of the input object!", call.=FALSE)
-  }
+  .checkArgProvided(x, "the name of the input object")
 
   ###################################################################################################
   #MODULE: EXTEND "type" argument to include "both" and enable valid alisases                       #
diff --git a/R/utils.R b/R/utils.R
index 63dc43901..faad6c424 100644
--- a/R/utils.R
+++ b/R/utils.R
@@ -16,13 +16,14 @@
 #' Verify that the provided data sources are of class 'DSConnection'.
 #'
 #' @param datasources A list of data sources.
+#' @param call The frame to report the error from.
 #' @importFrom cli cli_abort
 #' @author Tim Cadman, Genomics Coordination Centre, UMCG, Netherlands
 #' @noRd
-.verifyDatasources <- function(datasources) {
+.verifyDatasources <- function(datasources, call = parent.frame()) {
   isConnectionClass <- vapply(datasources, function(x) inherits(unlist(x), "DSConnection"), logical(1))
   if (!all(isConnectionClass)) {
-    cli_abort("The 'datasources' were expected to be a list of DSConnection-class objects")
+    cli_abort("{.arg datasources} must be a list of {.cls DSConnection} objects.", call = call)
   }
 }
 
@@ -30,12 +31,13 @@
 #'
 #' @param datasources An optional list of data sources. If not provided, the function will attempt
 #' to find available data sources.
+#' @param call The frame to report the error from.
 #' @return A list of verified data sources.
 #' @author Tim Cadman, Genomics Coordination Centre, UMCG, Netherlands
 #' @noRd
-.resolveDatasources <- function(datasources) {
+.resolveDatasources <- function(datasources, call = parent.frame()) {
   datasources <- .getDatasources(datasources)
-  .verifyDatasources(datasources)
+  .verifyDatasources(datasources, call = call)
   return(datasources)
 }
 
@@ -50,15 +52,18 @@
 #' @param field The name of the element holding the class. Default `"class"`.
 #' @param objectName Optional name of the input object, used to make the error
 #'   message specific. If `NULL` a generic message is used.
+#' @param call The frame to report the error from.
 #' @importFrom cli cli_abort
 #' @return Invisibly returns `NULL`. Called for its side effect (error checking).
 #' @author Tim Cadman, Genomics Coordination Centre, UMCG, Netherlands
 #' @noRd
-.checkClassConsistency <- function(results, field = "class", objectName = NULL) {
+.checkClassConsistency <- function(results, field = "class", objectName = NULL, call = parent.frame()) {
   classes <- lapply(results, function(r) r[[field]])
   if (length(unique(lapply(classes, sort))) > 1) {
-    subject <- if (is.null(objectName)) "The input object" else paste0("'", objectName, "'")
-    cli_abort("{subject} is not of the same class in all studies!")
+    if (is.null(objectName)) {
+      cli_abort("The input object must have the same class in all studies.", call = call)
+    }
+    cli_abort("{.val {objectName}} must have the same class in all studies.", call = call)
   }
 }
 
@@ -69,13 +74,14 @@
 #' user-friendly error.
 #'
 #' @param newobj A character string naming the object to be created server-side.
+#' @param call The frame to report the error from.
 #' @importFrom cli cli_abort
 #' @return Invisibly returns `NULL`. Called for its side effect (error checking).
 #' @author Tim Cadman, Genomics Coordination Centre, UMCG, Netherlands
 #' @noRd
-.checkNewobjName <- function(newobj) {
+.checkNewobjName <- function(newobj, call = parent.frame()) {
   if (!is.character(newobj) || length(newobj) != 1) {
-    cli_abort("'newobj' must be a single character string")
+    cli_abort("{.arg newobj} must be a single character string.", call = call)
   }
 }
 
@@ -88,32 +94,150 @@
 #' @param newobj A character string naming the object to be created server-side,
 #'   or `NULL` to use `default`.
 #' @param default The name to use when `newobj` is `NULL`.
+#' @param call The frame to report the error from.
 #' @return A validated, single character string.
 #' @author Tim Cadman, Genomics Coordination Centre, UMCG, Netherlands
 #' @noRd
-.resolveNewobjName <- function(newobj, default) {
+.resolveNewobjName <- function(newobj, default, call = parent.frame()) {
   if (is.null(newobj)) {
     newobj <- default
   }
-  .checkNewobjName(newobj)
+  .checkNewobjName(newobj, call = call)
   return(newobj)
 }
 
-#' Check That a Data Frame Name Is Provided
+#' Check That a Required Argument Is Provided
 #'
-#' Internal helper that checks whether a data frame or matrix object
-#' has been provided. If `NULL`, it aborts with a user-friendly error.
+#' Internal helper that aborts if a required argument is `NULL`, naming the
+#' argument as it was passed by the calling function.
 #'
-#' @param df A data.frame or matrix.
+#' @param x The argument to check.
+#' @param description What the argument must be, e.g. "the name of the input vector".
+#' @param call The frame to report the error from.
+#' @importFrom cli cli_abort
+#' @return Invisibly returns `NULL`. Called for its side effect (error checking).
+#' @author Tim Cadman, Genomics Coordination Centre, UMCG, Netherlands
+#' @noRd
+.checkArgProvided <- function(x, description, call = parent.frame()) {
+  if (is.null(x)) {
+    cli_abort("{.arg {deparse(substitute(x))}} must be {description}, not {.code NULL}.", call = call)
+  }
+}
+
+#' Check That Required Arguments Are All Set
+#'
+#' @param ... The arguments to check, named as the user knows them.
+#' @param call The frame to report the error from.
+#' @importFrom cli cli_abort
 #' @return Invisibly returns `NULL`. Called for its side effect (error checking).
 #' @author Tim Cadman, Genomics Coordination Centre, UMCG, Netherlands
 #' @noRd
-.checkDfNameProvided <- function(df) {
-  if(is.null(df)){
-    cli_abort("Please provide the name of a data.frame or matrix!")
+.checkArgsSet <- function(..., call = parent.frame()) {
+  args <- list(...)
+  if (any(vapply(args, is.null, logical(1)))) {
+    cli_abort("{.arg {names(args)}} must all be set.", call = call)
+  }
+}
+
+#' Convert a Seed to the Text Sent to the Server
+#'
+#' @param seed.as.integer A number, or `NULL` for no seed.
+#' @param call The frame to report the error from.
+#' @importFrom cli cli_abort
+#' @return The seed as a character string, or `"NULL"` when no seed was given.
+#' @author Tim Cadman, Genomics Coordination Centre, UMCG, Netherlands
+#' @noRd
+.seedAsText <- function(seed.as.integer, call = parent.frame()) {
+  if (is.null(seed.as.integer)) {
+    return("NULL")
+  }
+  if (!is.numeric(seed.as.integer)) {
+    cli_abort("{.arg seed.as.integer} must be an integer or {.code NULL}.", call = call)
+  }
+  return(as.character(seed.as.integer))
+}
+
+#' Warn About an Offset or Weights Written Into a Model Formula
+#'
+#' @param formula The model formula, as a character string or formula.
+#' @param call The frame to report the warning from.
+#' @importFrom cli cli_warn
+#' @return Invisibly returns `NULL`. Called for its side effect.
+#' @author Tim Cadman, Genomics Coordination Centre, UMCG, Netherlands
+#' @noRd
+.warnOffsetInFormula <- function(formula, call = parent.frame()) {
+  if (any(grepl("offset|weights", formula, ignore.case = TRUE))) {
+    cli_warn(c(
+      "You may have specified an offset or regression weights in the model formula.",
+      "i" = "Specify them separately with the {.arg offset} and {.arg weights} arguments."
+    ), call = call)
   }
 }
 
+#' Check That Each Object Has a Class That Can Be Combined
+#'
+#' @param datasources A list of data sources.
+#' @param x The names of the server-side objects.
+#' @param call The frame to report the error from.
+#' @importFrom cli cli_abort
+#' @return Invisibly returns `NULL`. Called for its side effect (error checking).
+#' @author Tim Cadman, Genomics Coordination Centre, UMCG, Netherlands
+#' @noRd
+.checkObjectClasses <- function(datasources, x, call = parent.frame()) {
+  allowed <- c("data.frame", "matrix", "numeric", "integer", "character", "factor", "logical")
+  for (name in x) {
+    if (!any(allowed %in% checkClass(datasources, name))) {
+      cli_abort("Each object must be of class {.or {.val {allowed}}}.", call = call)
+    }
+  }
+}
+
+#' Check That Objects to Be Bound Together Fit in Every Study
+#'
+#' Warns if column names are duplicated, and aborts if the objects differ in
+#' their number of rows.
+#'
+#' @param datasources A list of data sources.
+#' @param x The names of the server-side objects.
+#' @param call The frame to report the error from.
+#' @importFrom cli cli_abort cli_warn
+#' @return Invisibly returns `NULL`. Called for its side effect.
+#' @author Tim Cadman, Genomics Coordination Centre, UMCG, Netherlands
+#' @noRd
+.checkMultiObjectConsistency <- function(datasources, x, call = parent.frame()) {
+  isTable <- vapply(x, function(name) any(checkClass(datasources, name) %in% c("data.frame", "matrix")), logical(1))
+  for (j in seq_along(datasources)) {
+    study <- datasources[j]
+    columns <- lapply(seq_along(x), function(i) {
+      if (isTable[[i]]) ds.colnames(x = x[i], datasources = study) else as.character(x[i])
+    })
+    if (anyDuplicated(unlist(columns)) != 0) {
+      cli_warn("Some column names in study {j} are duplicated, so a suffix {.val .k} is added to the kth replicate.", call = call)
+    }
+    rows <- vapply(seq_along(x), function(i) {
+      if (isTable[[i]]) {
+        return(as.numeric(ds.dim(x = x[i], type = "split", datasources = study)[[1]][1]))
+      }
+      as.numeric(ds.length(x[i], type = "split", datasources = study)[[1]])
+    }, numeric(1))
+    if (any(rows != rows[1])) {
+      cli_abort("All components must have the same number of rows.", call = call)
+    }
+  }
+}
+
+#' Abort Because an Argument Is Not One of the Allowed Values
+#'
+#' @param argName The name of the argument.
+#' @param choices A character vector of the allowed values.
+#' @param call The frame to report the error from.
+#' @importFrom cli cli_abort cli_inform cli_verbatim cli_warn
+#' @author Tim Cadman, Genomics Coordination Centre, UMCG, Netherlands
+#' @noRd
+.abortInvalidChoice <- function(argName, choices, call = parent.frame()) {
+  cli_abort("{.arg {argName}} must be {.or {.val {choices}}}.", call = call)
+}
+
 #' Expand an Argument to One Value per Study
 #'
 #' Arguments that may differ between studies can be given either as a single
@@ -122,16 +246,17 @@
 #' @param values A vector of length 1 or `numStudies`.
 #' @param argName The name of the argument, used in the error message.
 #' @param numStudies The number of studies being analysed.
+#' @param call The frame to report the error from.
 #' @importFrom cli cli_abort
 #' @return A vector of length `numStudies`.
 #' @author Tim Cadman, Genomics Coordination Centre, UMCG, Netherlands
 #' @noRd
-.expandToStudies <- function(values, argName, numStudies) {
+.expandToStudies <- function(values, argName, numStudies, call = parent.frame()) {
   if (length(values) == 1) {
     return(rep(values, numStudies))
   }
   if (length(values) != numStudies) {
-    cli_abort("'{argName}' must be length 1 or one value per study")
+    cli_abort("{.arg {argName}} must have length 1 or one value per study.", call = call)
   }
   return(values)
 }
diff --git a/tests/testthat/test-_-utils.R b/tests/testthat/test-_-utils.R
new file mode 100644
index 000000000..1586c8e0c
--- /dev/null
+++ b/tests/testthat/test-_-utils.R
@@ -0,0 +1,64 @@
+#
+# Tests
+#
+
+# context("utils::.checkArgProvided")
+test_that(".checkArgProvided names the argument and reports the calling function", {
+    check <- function(x) .checkArgProvided(x, "the name of the input vector")
+
+    expect_null(check("a"))
+    error <- expect_error(check(NULL), "`x` must be the name of the input vector")
+    expect_equal(error$call, quote(check(NULL)))
+})
+
+# context("utils::.abortInvalidChoice")
+test_that(".abortInvalidChoice lists the allowed values", {
+    expect_error(.abortInvalidChoice("type", c("combine", "split")), "`type` must be \"combine\" or \"split\"")
+    expect_error(.abortInvalidChoice("type", c("both", "combine", "split")), "`type` must be \"both\", \"combine\", or \"split\"")
+})
+
+# context("utils::.resolveNewobjName")
+test_that(".resolveNewobjName applies the default before validating", {
+    expect_equal(.resolveNewobjName(NULL, "x.newobj"), "x.newobj")
+    expect_equal(.resolveNewobjName("my.obj", "x.newobj"), "my.obj")
+})
+
+test_that(".resolveNewobjName rejects anything but a single character string", {
+    expect_error(.resolveNewobjName(23, "x.newobj"), "`newobj` must be a single character string")
+    expect_error(.resolveNewobjName(c("a", "b"), "x.newobj"), "`newobj` must be a single character string")
+})
+
+# context("utils::.verifyDatasources")
+test_that(".verifyDatasources rejects objects that are not connections", {
+    expect_error(.verifyDatasources(list(1)), "`datasources` must be a list of <DSConnection> objects")
+})
+
+# context("utils::.checkClassConsistency")
+test_that(".checkClassConsistency compares the chosen field across studies", {
+    same <- list(a = list(class = "numeric"), b = list(class = "numeric"))
+    different <- list(a = list(class = "numeric"), b = list(class = "factor"))
+
+    expect_null(.checkClassConsistency(same))
+    expect_error(.checkClassConsistency(different), "The input object must have the same class")
+    expect_error(.checkClassConsistency(different, objectName = "D"), "\"D\" must have the same class")
+})
+
+# context("utils::.seedAsText")
+test_that(".seedAsText converts the seed and rejects anything that isn't a number", {
+    expect_equal(.seedAsText(NULL), "NULL")
+    expect_equal(.seedAsText(27), "27")
+    expect_error(.seedAsText("a"), "`seed.as.integer` must be an integer or `NULL`")
+})
+
+# context("utils::.checkArgsSet")
+test_that(".checkArgsSet names every argument", {
+    expect_null(.checkArgsSet(a = 1, b = 2))
+    expect_error(.checkArgsSet(a = NULL, b = 2), "`a` and `b` must all be set")
+})
+
+# context("utils::.warnOffsetInFormula")
+test_that(".warnOffsetInFormula looks for an offset or weights in the formula", {
+    expect_no_warning(.warnOffsetInFormula("y~x"))
+    expect_warning(.warnOffsetInFormula("y~offset(x)"), "offset or regression weights")
+    expect_warning(.warnOffsetInFormula("y~x+WEIGHTS"), "offset or regression weights")
+})
diff --git a/tests/testthat/test-arg-ds.Boole.R b/tests/testthat/test-arg-ds.Boole.R
index d8fb3bedf..eecb996c3 100644
--- a/tests/testthat/test-arg-ds.Boole.R
+++ b/tests/testthat/test-arg-ds.Boole.R
@@ -21,10 +21,10 @@ connect.studies.dataset.cnsim(list("LAB_TSC", "LAB_TRIG"))
 
 # context("ds.Boole::arg::test errors")
 test_that("Boole_erros", {
-    expect_error(ds.Boole(), "Please provide the name of the column or scalar that holds V1!", fixed=TRUE)
-    expect_error(ds.Boole(V1="D$LAB_TSC"), "Please provide the name of a column or scalar holding V2 or declare a scalar in character format: eg '3'", fixed=TRUE)
-    expect_error(ds.Boole(V1="D$LAB_TSC", V2="LAB_TRIG"), "Please provide a Boolean operator in character format: eg '==' or '>=' or '<' or '!='", fixed=TRUE)
-    expect_error(ds.Boole(V1="D$LAB_TSC", V2="LAB_TRIG", Boolean.operator="==", na.assign=2), "Error: na.assign must be a character string taking value 'NA', '0' or '1'- if <na.action> not specified default is 'NA'", fixed=TRUE)
+    expect_error(ds.Boole(), "must be the name of the column or scalar that holds V1", fixed=TRUE)
+    expect_error(ds.Boole(V1="D$LAB_TSC"), "must be the name of a column or scalar that holds V2", fixed=TRUE)
+    expect_error(ds.Boole(V1="D$LAB_TSC", V2="LAB_TRIG"), "must be a Boolean operator in character format", fixed=TRUE)
+    expect_error(ds.Boole(V1="D$LAB_TSC", V2="LAB_TRIG", Boolean.operator="==", na.assign=2), "must be \"NA\", \"0\", or \"1\"", fixed=TRUE)
     expect_error(ds.Boole(V1="D$LAB_TSC", V2="LAB_TRIG", Boolean.operator="AA"), "An unrecognized Boolean operator, AA, has provide", fixed=TRUE)
 })
 
diff --git a/tests/testthat/test-arg-ds.abs.R b/tests/testthat/test-arg-ds.abs.R
index cfe0a49aa..c09eb9171 100644
--- a/tests/testthat/test-arg-ds.abs.R
+++ b/tests/testthat/test-arg-ds.abs.R
@@ -10,7 +10,7 @@ connect.studies.dataset.cnsim(list("LAB_TSC"))
 
 # context("ds.abs::arg::test errors")
 test_that("abs_errors", {
-    expect_error(ds.abs(), "Please provide the name of the input object!", fixed=TRUE)
+    expect_error(ds.abs(), "must be the name of the input object", fixed=TRUE)
 })
 
 #
diff --git a/tests/testthat/test-arg-ds.asCharacter.R b/tests/testthat/test-arg-ds.asCharacter.R
index 8d7d35449..b3de6cbe9 100644
--- a/tests/testthat/test-arg-ds.asCharacter.R
+++ b/tests/testthat/test-arg-ds.asCharacter.R
@@ -21,7 +21,7 @@ connect.discordant.dataset.simple(list("A", "B", "C"))
 
 # context("ds.asCharacter::arg::test errors")
 test_that("asCharacter_erros", {
-    expect_error(ds.asCharacter(), "Please provide the name of the input vector!", fixed=TRUE)
+    expect_error(ds.asCharacter(), "must be the name of the input vector", fixed=TRUE)
 })
 
 # context("ds.asCharacter::arg::discordant errors")
diff --git a/tests/testthat/test-arg-ds.asDataMatrix.R b/tests/testthat/test-arg-ds.asDataMatrix.R
index ca65f6cb0..c102de734 100644
--- a/tests/testthat/test-arg-ds.asDataMatrix.R
+++ b/tests/testthat/test-arg-ds.asDataMatrix.R
@@ -21,7 +21,7 @@ connect.studies.dataset.cnsim(list("LAB_TSC"))
 
 # context("ds.asDataMatrix::arg::test errors")
 test_that("asDataMatrix_erros", {
-    expect_error(ds.asDataMatrix(), "Please provide the name of the input vector!", fixed=TRUE)
+    expect_error(ds.asDataMatrix(), "must be the name of the input vector", fixed=TRUE)
 })
 
 #
diff --git a/tests/testthat/test-arg-ds.asFactor.R b/tests/testthat/test-arg-ds.asFactor.R
index a264b040a..5f433fdcb 100644
--- a/tests/testthat/test-arg-ds.asFactor.R
+++ b/tests/testthat/test-arg-ds.asFactor.R
@@ -21,7 +21,7 @@ connect.studies.dataset.cnsim(list("LAB_TSC"))
 
 # context("ds.asFactor::arg::test errors")
 test_that("asFactor_erros", {
-    expect_error(ds.asFactor(), "Please provide the name of the variable that is to be converted to a factor e.g. 'varname'", fixed=TRUE)
+    expect_error(ds.asFactor(), "must be the name of the variable to convert", fixed=TRUE)
     expect_error(ds.asFactor(input.var.name=1), "Please provide the name of the variable that is to be converted to a factor in character format e.g. 'varname'", fixed=TRUE)
     expect_error(ds.asFactor(input.var.name=NA), "Please provide the name of the variable that is to be converted to a factor in character format e.g. 'varname'", fixed=TRUE)
 })
diff --git a/tests/testthat/test-arg-ds.asInteger.R b/tests/testthat/test-arg-ds.asInteger.R
index c6305012e..fb11796ad 100644
--- a/tests/testthat/test-arg-ds.asInteger.R
+++ b/tests/testthat/test-arg-ds.asInteger.R
@@ -21,7 +21,7 @@ connect.studies.dataset.cnsim(list("LAB_TSC"))
 
 # context("ds.asInteger::arg::test errors")
 test_that("asInteger_erros", {
-    expect_error(ds.asInteger(), "Please provide the name of the input vector!", fixed=TRUE)
+    expect_error(ds.asInteger(), "must be the name of the input vector", fixed=TRUE)
 })
 
 #
diff --git a/tests/testthat/test-arg-ds.asList.R b/tests/testthat/test-arg-ds.asList.R
index 926401881..4deb3e771 100644
--- a/tests/testthat/test-arg-ds.asList.R
+++ b/tests/testthat/test-arg-ds.asList.R
@@ -21,7 +21,7 @@ connect.studies.dataset.cnsim(list("LAB_TSC"))
 
 # context("ds.asList::arg::test errors")
 test_that("asList_erros", {
-    expect_error(ds.asList(), "Please provide the name of the input vector!", fixed=TRUE)
+    expect_error(ds.asList(), "must be the name of the input vector", fixed=TRUE)
 })
 
 #
diff --git a/tests/testthat/test-arg-ds.asLogical.R b/tests/testthat/test-arg-ds.asLogical.R
index 39056cc38..18f06c355 100644
--- a/tests/testthat/test-arg-ds.asLogical.R
+++ b/tests/testthat/test-arg-ds.asLogical.R
@@ -21,7 +21,7 @@ connect.studies.dataset.cnsim(list("LAB_TSC"))
 
 # context("ds.asLogical::arg::test errors")
 test_that("asLogical_erros", {
-    expect_error(ds.asLogical(), "Please provide the name of the input vector!", fixed=TRUE)
+    expect_error(ds.asLogical(), "must be the name of the input vector", fixed=TRUE)
 })
 
 #
diff --git a/tests/testthat/test-arg-ds.asMatrix.R b/tests/testthat/test-arg-ds.asMatrix.R
index 4a199dd08..af186d4fc 100644
--- a/tests/testthat/test-arg-ds.asMatrix.R
+++ b/tests/testthat/test-arg-ds.asMatrix.R
@@ -21,7 +21,7 @@ connect.studies.dataset.cnsim(list("LAB_TSC"))
 
 # context("ds.asMatrix::arg::test errors")
 test_that("asMatrix_erros", {
-    expect_error(ds.asMatrix(), "Please provide the name of the input vector!", fixed=TRUE)
+    expect_error(ds.asMatrix(), "must be the name of the input vector", fixed=TRUE)
 })
 
 #
diff --git a/tests/testthat/test-arg-ds.asNumeric.R b/tests/testthat/test-arg-ds.asNumeric.R
index 276260751..d8fe241bc 100644
--- a/tests/testthat/test-arg-ds.asNumeric.R
+++ b/tests/testthat/test-arg-ds.asNumeric.R
@@ -21,7 +21,7 @@ connect.studies.dataset.cnsim(list("LAB_TSC"))
 
 # context("ds.asNumeric::arg::test errors")
 test_that("asNumeric_erros", {
-    expect_error(ds.asNumeric(), "Please provide the name of the input vector!", fixed=TRUE)
+    expect_error(ds.asNumeric(), "must be the name of the input vector", fixed=TRUE)
 })
 
 #
diff --git a/tests/testthat/test-arg-ds.assign.R b/tests/testthat/test-arg-ds.assign.R
index 4fbd06c42..41bbbb307 100644
--- a/tests/testthat/test-arg-ds.assign.R
+++ b/tests/testthat/test-arg-ds.assign.R
@@ -21,7 +21,7 @@ connect.studies.dataset.cnsim(list("LAB_TSC"))
 
 # context("ds.assign::arg::test errors")
 test_that("assign_erros", {
-    expect_error(ds.assign(), "Please give the name of object to assign or an expression to evaluate and assign.!\n")
+    expect_error(ds.assign(), "must be the name of the object to assign")
 })
 
 #
diff --git a/tests/testthat/test-arg-ds.auc.R b/tests/testthat/test-arg-ds.auc.R
index 55978417a..a37b7526e 100644
--- a/tests/testthat/test-arg-ds.auc.R
+++ b/tests/testthat/test-arg-ds.auc.R
@@ -25,8 +25,8 @@ connect.studies.dataset.cnsim(list("LAB_TSC"))
 
 test_that("ds.auc errors for null pred or y", {
   
-    expect_error(ds.auc(pred=NULL, y='y'), "Please provide the name of the vector with predicted values", fixed=TRUE)
-    expect_error(ds.auc(pred='pred', y=NULL), "Please provide the name of the outcome variable", fixed=TRUE)
+    expect_error(ds.auc(pred=NULL, y='y'), "must be the name of the vector of predicted values", fixed=TRUE)
+    expect_error(ds.auc(pred='pred', y=NULL), "must be the name of the outcome variable", fixed=TRUE)
   
 })
 
diff --git a/tests/testthat/test-arg-ds.c.R b/tests/testthat/test-arg-ds.c.R
index 7a85cecb4..50b674b6f 100644
--- a/tests/testthat/test-arg-ds.c.R
+++ b/tests/testthat/test-arg-ds.c.R
@@ -21,7 +21,7 @@ connect.studies.dataset.cnsim(list("LAB_TSC"))
 
 # context("ds.c::arg::test errors")
 test_that("simple c errors", {
-    expect_error(ds.c(), "x=NULL. Please provide the names of the objects to concatenate!")
+    expect_error(ds.c(), "must be the names of the objects to concatenate")
 })
 
 #
diff --git a/tests/testthat/test-arg-ds.cbind.R b/tests/testthat/test-arg-ds.cbind.R
index a51988136..d32131c3d 100644
--- a/tests/testthat/test-arg-ds.cbind.R
+++ b/tests/testthat/test-arg-ds.cbind.R
@@ -23,8 +23,8 @@ connect.studies.dataset.cnsim(list("LAB_TSC"))
 test_that("cbind_erros", {
     ds.asList(x='D$LAB_TSC', newobj="as_list")
 
-    expect_error(ds.cbind(), "Please provide a vector of character strings holding the name of the input elements!", fixed=TRUE)
-    expect_error(ds.cbind(x="as_list", DataSHIELD.checks=TRUE), "Only objects of type 'data.frame', 'matrix', 'numeric', 'integer', 'character', 'factor' and 'logical' are allowed.", fixed=TRUE)
+    expect_error(ds.cbind(), "must be a vector of the names of the input elements", fixed=TRUE)
+    expect_error(ds.cbind(x="as_list", DataSHIELD.checks=TRUE), "Each object must be of class", fixed=TRUE)
 })
 
 #
diff --git a/tests/testthat/test-arg-ds.changeRefGroup.R b/tests/testthat/test-arg-ds.changeRefGroup.R
index e1a9977be..1f72dc8be 100644
--- a/tests/testthat/test-arg-ds.changeRefGroup.R
+++ b/tests/testthat/test-arg-ds.changeRefGroup.R
@@ -21,8 +21,8 @@ connect.studies.dataset.cnsim(list("DIS_AMI", "LAB_TSC"))
 
 # context("ds.changeRefGroup::arg::test errors")
 test_that("changeRefGroup_erros", {
-    expect_error(ds.changeRefGroup(), "Please provide the name of a vector of type factor!")
-    expect_error(ds.changeRefGroup(x="D$DIS_AMI"), " You must indicate a reference level - set the parameter 'ref'.")
+    expect_error(ds.changeRefGroup(), "must be the name of a factor")
+    expect_error(ds.changeRefGroup(x="D$DIS_AMI"), "must be a reference level")
 
     expect_error(ds.changeRefGroup(x="D$LAB_TSC", ref="LAB_TSC"), "There are some DataSHIELD errors, list them with datashield.errors()", fixed=TRUE)
 
diff --git a/tests/testthat/test-arg-ds.class.R b/tests/testthat/test-arg-ds.class.R
index c0bf5c7dd..dfe92485d 100644
--- a/tests/testthat/test-arg-ds.class.R
+++ b/tests/testthat/test-arg-ds.class.R
@@ -21,7 +21,7 @@ connect.studies.dataset.cnsim(list("LAB_TSC"))
 
 # context("ds.class::arg::test errors")
 test_that("class_erros", {
-    expect_error(ds.class(), "Please provide the name of the input object!", fixed=TRUE)
+    expect_error(ds.class(), "must be the name of the input object", fixed=TRUE)
 })
 
 #
diff --git a/tests/testthat/test-arg-ds.completeCases.R b/tests/testthat/test-arg-ds.completeCases.R
index 8bb997338..81661f3f2 100644
--- a/tests/testthat/test-arg-ds.completeCases.R
+++ b/tests/testthat/test-arg-ds.completeCases.R
@@ -21,8 +21,7 @@ connect.studies.dataset.cnsim(list("LAB_TSC"))
 
 # context("ds.completeCases::arg::test errors")
 test_that("completeCases_errors", {
-  res <- ds.completeCases()
-  expect_equal(res, "Error: x1 must be a character string naming a serverside data.frame, matrix or vector", fixed = TRUE)
+  expect_error(ds.completeCases(), "must be a character string that names a server-side")
 })
 
 #
diff --git a/tests/testthat/test-arg-ds.cor.R b/tests/testthat/test-arg-ds.cor.R
index 25acd2f3b..5d6156a4a 100644
--- a/tests/testthat/test-arg-ds.cor.R
+++ b/tests/testthat/test-arg-ds.cor.R
@@ -21,8 +21,8 @@ connect.studies.dataset.cnsim(list("LAB_TSC", "LAB_TRIG"))
 
 # context("ds.cor::arg::test errors")
 test_that("cor_erros", {
-    expect_error(ds.cor(), 'x=NULL. Please provide the name of a matrix or dataframe or the names of two numeric vectors!', fixed=TRUE)
-    expect_error(ds.cor(x='D$LAB_TSC', y='D$LAB_TRIG', type='datashield'), 'Function argument "type" has to be either "combine" or "split"', fixed=TRUE)
+    expect_error(ds.cor(), "must be the name of a matrix, data.frame or numeric vector", fixed=TRUE)
+    expect_error(ds.cor(x='D$LAB_TSC', y='D$LAB_TRIG', type='datashield'), "must be \"combine\" or \"split\"", fixed=TRUE)
 })
 
 #
diff --git a/tests/testthat/test-arg-ds.corTest.R b/tests/testthat/test-arg-ds.corTest.R
index 76adc6f15..ba1711b20 100644
--- a/tests/testthat/test-arg-ds.corTest.R
+++ b/tests/testthat/test-arg-ds.corTest.R
@@ -22,8 +22,8 @@ connect.studies.dataset.survival(list("survtime", "time.id"))
 # context("ds.corTest::arg")
 
 test_that("simple arg test", {
-    expect_error(ds.corTest(), "x=NULL. Please provide the names of the 1st numeric vector!", fixed=TRUE)
-    expect_error(ds.corTest(x="D$survtime"), "y=NULL. Please provide the names of the 2nd numeric vector!", fixed=TRUE)
+    expect_error(ds.corTest(), "must be the name of the first numeric vector", fixed=TRUE)
+    expect_error(ds.corTest(x="D$survtime"), "must be the name of the second numeric vector", fixed=TRUE)
 })
 
 #
diff --git a/tests/testthat/test-arg-ds.cov.R b/tests/testthat/test-arg-ds.cov.R
index d713fe366..341d74116 100644
--- a/tests/testthat/test-arg-ds.cov.R
+++ b/tests/testthat/test-arg-ds.cov.R
@@ -21,8 +21,8 @@ connect.studies.dataset.cnsim(list("LAB_TSC", "LAB_TRIG"))
 
 # context("ds.cov::arg::test errors")
 test_that("cov_erros", {
-    expect_error(ds.cov(), 'x=NULL. Please provide the name of a matrix or dataframe or the names of two numeric vectors!', fixed=TRUE)
-    expect_error(ds.cov(x='D$LAB_TSC', y='D$LAB_TRIG', type='datashield'), 'Function argument "type" has to be either "combine" or "split"', fixed=TRUE)
+    expect_error(ds.cov(), "must be the name of a matrix, data.frame or numeric vector", fixed=TRUE)
+    expect_error(ds.cov(x='D$LAB_TSC', y='D$LAB_TRIG', type='datashield'), "must be \"combine\" or \"split\"", fixed=TRUE)
 })
 
 #
diff --git a/tests/testthat/test-arg-ds.dataFrame.R b/tests/testthat/test-arg-ds.dataFrame.R
index 33fa65cf6..1f966e4f1 100644
--- a/tests/testthat/test-arg-ds.dataFrame.R
+++ b/tests/testthat/test-arg-ds.dataFrame.R
@@ -21,10 +21,10 @@ connect.studies.dataset.cnsim(list("LAB_TSC"))
 
 # context("ds.dataFrame::arg::test errors")
 test_that("dataframe_erros", {
-    expect_error(ds.dataFrame(), "Please provide the name of the list that holds the input vectors!", fixed=TRUE)
+    expect_error(ds.dataFrame(), "must be the name of the list that holds the input vectors", fixed=TRUE)
 
     ds.asList(x='D$LAB_TSC', newobj="as_list")
-    expect_error(ds.dataFrame("as_list", DataSHIELD.checks=TRUE), "Only objects of type 'data.frame', 'matrix', 'numeric', 'integer', 'character', 'factor' and 'logical' are allowed.", fixed=TRUE)
+    expect_error(ds.dataFrame("as_list", DataSHIELD.checks=TRUE), "Each object must be of class", fixed=TRUE)
 })
 
 #
diff --git a/tests/testthat/test-arg-ds.dataFrameSubset.R b/tests/testthat/test-arg-ds.dataFrameSubset.R
index 0799acf9f..9119fe810 100644
--- a/tests/testthat/test-arg-ds.dataFrameSubset.R
+++ b/tests/testthat/test-arg-ds.dataFrameSubset.R
@@ -28,7 +28,7 @@ test_that("setup", {
 
 # context("ds.dataFrameSubset::arg::missing 'ds.name' arg errors")
 test_that("dataFrameSubset_erros", {
-    expect_error(ds.dataFrameSubset(), "Please provide the name of the data.frame to be subsetted as a character string: eg 'xxx'", fixed=TRUE)
+    expect_error(ds.dataFrameSubset(), "must be the name of the data.frame to subset", fixed=TRUE)
 })
 
 # context("ds.dataFrameSubset::arg::missing 'V1' arg error")
diff --git a/tests/testthat/test-arg-ds.dim.R b/tests/testthat/test-arg-ds.dim.R
index 2fa7d228c..4ebcfc3bd 100644
--- a/tests/testthat/test-arg-ds.dim.R
+++ b/tests/testthat/test-arg-ds.dim.R
@@ -21,8 +21,8 @@ connect.studies.dataset.cnsim(list("LAB_TSC"))
 
 # context("ds.dim::arg::test errors")
 test_that("dim_erros", {
-    expect_error(ds.dim(), "Please provide the name of a data.frame or matrix!", fixed=TRUE)
-    expect_error(ds.dim(x="D", type = "other"), 'Function argument "type" has to be either "both", "combine" or "split"', fixed=TRUE)
+    expect_error(ds.dim(), "must be the name of a data.frame or matrix", fixed=TRUE)
+    expect_error(ds.dim(x="D", type = "other"), "must be \"both\", \"combine\", or \"split\"", fixed=TRUE)
 })
 
 #
diff --git a/tests/testthat/test-arg-ds.exists.R b/tests/testthat/test-arg-ds.exists.R
index 8ae2070d3..2ab9f06df 100644
--- a/tests/testthat/test-arg-ds.exists.R
+++ b/tests/testthat/test-arg-ds.exists.R
@@ -21,7 +21,7 @@ connect.studies.dataset.cnsim(list("LAB_TSC"))
 
 # context("ds.exists::arg::test errors")
 test_that("simple exists errors", {
-    expect_error(ds.exists(), "Please provide the name of the input object!")
+    expect_error(ds.exists(), "must be the name of the input object")
 })
 
 #
diff --git a/tests/testthat/test-arg-ds.exp.R b/tests/testthat/test-arg-ds.exp.R
index c851bba34..c947b1d72 100644
--- a/tests/testthat/test-arg-ds.exp.R
+++ b/tests/testthat/test-arg-ds.exp.R
@@ -21,7 +21,7 @@ connect.studies.dataset.cnsim(list("LAB_TSC"))
 
 # context("ds.exp::arg::test errors")
 test_that("exp_erros", {
-    expect_error(ds.exp(), "Please provide the name of the input object!", fixed=TRUE)
+    expect_error(ds.exp(), "must be the name of the input object", fixed=TRUE)
 })
 
 #
diff --git a/tests/testthat/test-arg-ds.gamlss.R b/tests/testthat/test-arg-ds.gamlss.R
index c24f41efb..609c281c4 100644
--- a/tests/testthat/test-arg-ds.gamlss.R
+++ b/tests/testthat/test-arg-ds.gamlss.R
@@ -21,8 +21,8 @@ connect.studies.dataset.gamlss(list("e3_bw", "e3_gac_None"))
 
 # context("ds.gamlss::arg::test errors")
 test_that("gamlss_errors", {
-    expect_error(ds.gamlss(), " Please provide a valid formula!", fixed=TRUE)
-    expect_error(ds.gamlss(formula="e3_bw ~ e3_gac_None", method="RG"), "Argument 'method' must be either 'RS', 'CG' or 'mixed'", fixed=TRUE)
+    expect_error(ds.gamlss(), "must be a valid formula", fixed=TRUE)
+    expect_error(ds.gamlss(formula="e3_bw ~ e3_gac_None", method="RG"), "must be \"RS\", \"CG\", or \"mixed\"", fixed=TRUE)
     expect_error(ds.gamlss(formula="e3_bw ~ e3_gac_None", method="RS", centiles=TRUE), "Provide the name of the explanatory variable in 'xvar' argument", fixed=TRUE)
 })
 
diff --git a/tests/testthat/test-arg-ds.glm.R b/tests/testthat/test-arg-ds.glm.R
index fbf1a880f..e4221bbcd 100644
--- a/tests/testthat/test-arg-ds.glm.R
+++ b/tests/testthat/test-arg-ds.glm.R
@@ -21,8 +21,8 @@ connect.studies.dataset.cnsim(list("LAB_TSC"))
 
 # context("ds.glm::arg::test errors")
 test_that("glm_errors", {
-    expect_error(ds.glm(), " Please provide a valid regression formula!", fixed=TRUE)
-    expect_error(ds.glm("D$LAB_TSC~D$LAB_TSC"), " Please provide a valid 'family' argument!", fixed=TRUE)
+    expect_error(ds.glm(), "must be a valid regression formula", fixed=TRUE)
+    expect_error(ds.glm("D$LAB_TSC~D$LAB_TSC"), "must be a valid family", fixed=TRUE)
 })
 
 #
diff --git a/tests/testthat/test-arg-ds.glmPredict.R b/tests/testthat/test-arg-ds.glmPredict.R
index f0a2f2857..dab0976fc 100644
--- a/tests/testthat/test-arg-ds.glmPredict.R
+++ b/tests/testthat/test-arg-ds.glmPredict.R
@@ -21,7 +21,7 @@ connect.studies.dataset.cnsim(list("LAB_TSC", "LAB_TRIG", "DIS_AMI", "DIS_DIAB",
 
 # context("ds.glmPredict::arg::test _glmname_ arg is correct object")
 test_that("glmPredict_errors", {
-  expect_error(ds.glmPredict(), "<glmname> is not set, please specify it as a character string containing the name of a valid glm class object on the serverside", fixed=TRUE)
+  expect_error(ds.glmPredict(), "must be the name of a glm object on the server", fixed=TRUE)
 })
 
 # context("ds.glmPredict::arg::setting up glm obj for further testing")
@@ -47,7 +47,7 @@ test_that("glmPredict_errors", {
 # context("ds.glmPredict::arg::test _output.type_ arg is correct object")
 test_that("glmPredict_errors", {
   expect_error(ds.glmPredict("gaussian.glmslma.obj", newdataname = NULL, output.type = NULL), "missing value where TRUE/FALSE needed", fixed=TRUE)
-  expect_error(ds.glmPredict("gaussian.glmslma.obj", newdataname = NULL, output.type = 'blah'), "<output.type> is not correctly set, please specify it as one of three character strings: 'link', 'response', or 'terms'", fixed=TRUE)
+  expect_error(ds.glmPredict("gaussian.glmslma.obj", newdataname = NULL, output.type = 'blah'), "must be \"link\", \"response\", or \"terms\"", fixed=TRUE)
 })
 
 # context("ds.glmPredict::arg::test _se.fit_ arg is correct object")
@@ -71,7 +71,7 @@ test_that("glmPredict_errors", {
 
 # context("ds.glmPredict::arg::test _na.action_ arg is correct object")
 test_that("glmPredict_errors", {
-  expect_error(ds.glmPredict("gaussian.glmslma.obj", newdataname = NULL, output.type = "response", se.fit = FALSE, dispersion = NULL, terms=NULL, na.action= "na.other"), "<na.action> is not correctly set, please specify it as one of four character strings: 'na.fail', 'na.omit', 'na.exclude' or 'na.pass'", fixed = TRUE)
+  expect_error(ds.glmPredict("gaussian.glmslma.obj", newdataname = NULL, output.type = "response", se.fit = FALSE, dispersion = NULL, terms=NULL, na.action= "na.other"), "must be \"na.fail\"", fixed = TRUE)
 })
 
 
diff --git a/tests/testthat/test-arg-ds.glmSLMA.R b/tests/testthat/test-arg-ds.glmSLMA.R
index 4180f91af..29d072cfa 100644
--- a/tests/testthat/test-arg-ds.glmSLMA.R
+++ b/tests/testthat/test-arg-ds.glmSLMA.R
@@ -21,7 +21,7 @@ connect.studies.dataset.cnsim(list("LAB_TSC"))
 
 # context("ds.glmSLMA::arg::test errors")
 test_that("glmSLMA_errors", {
-  expect_error(ds.glmSLMA(), " Please provide a valid regression formula!", fixed=TRUE)
+  expect_error(ds.glmSLMA(), "must be a valid regression formula", fixed=TRUE)
   
   expect_error(ds.glmSLMA('D$LAB_TSC~D$LAB_TRIG', family="gaussian", newobj="gaussian.glmslma.obj"), "There are some DataSHIELD errors, list them with datashield.errors()", fixed=TRUE)
   res.errors<-datashield.errors()
diff --git a/tests/testthat/test-arg-ds.glmerSLMA.R b/tests/testthat/test-arg-ds.glmerSLMA.R
index 36c80bb5b..52421dcf1 100644
--- a/tests/testthat/test-arg-ds.glmerSLMA.R
+++ b/tests/testthat/test-arg-ds.glmerSLMA.R
@@ -27,7 +27,7 @@ test_that("setup", {
 
 # context("ds.glmerSLMA::arg::testing")
 test_that("simple glmerSLMA tesing (mis)use of arguments", {
-    expect_error(ds.glmerSLMA(formula = 'incid_rate ~ trtGrp + Male + (1|idDoctor)', dataName = 'D'), " Please provide a valid 'family' argument!", fixed=TRUE)
+    expect_error(ds.glmerSLMA(formula = 'incid_rate ~ trtGrp + Male + (1|idDoctor)', dataName = 'D'), "must be a valid family", fixed=TRUE)
 
     expect_error(ds.glmerSLMA(formula = 'diab_dis ~ trtGrp + Male + (1|idDoctor)', family='poisson', dataName = 'D'), "There are some DataSHIELD errors, list them with datashield.errors()", fixed=TRUE)
 
@@ -37,8 +37,7 @@ test_that("simple glmerSLMA tesing (mis)use of arguments", {
     expect_length(errs$sim2, 0)
     expect_length(errs$sim3, 0)
 
-    res <- ds.glmerSLMA(formula = 'incid_rate ~ trtGrp + Male + (1|idDoctor)', family='poisson', dataName = 'D', control_type = 'xtol_rel')
-    expect_equal(res$errorMessage, "ERROR: if control_type is non-null, you must specify a valid control_value eg control_value<-1.0e-7",fixed=TRUE)
+    expect_error(ds.glmerSLMA(formula = 'incid_rate ~ trtGrp + Male + (1|idDoctor)', family='poisson', dataName = 'D', control_type = 'xtol_rel'), "must be set when")
     expect_error(ds.glmerSLMA(formula = 'incid_rate ~ trtGrp + Male + (1|idDoctor)', family='poisson', dataName = 'D', control_type = 'check.conv.grad',control_value = 'nothing'), "There are some DataSHIELD errors, list them with datashield.errors()", fixed=TRUE)
 
     errs <- datashield.errors()
@@ -47,7 +46,7 @@ test_that("simple glmerSLMA tesing (mis)use of arguments", {
     expect_length(errs$sim2, 0)
     expect_length(errs$sim3, 0)
 
-    expect_error(ds.glmerSLMA(), " Please provide a valid regression formula!", fixed=TRUE)
+    expect_error(ds.glmerSLMA(), "must be a valid regression formula", fixed=TRUE)
 })
 
 #
diff --git a/tests/testthat/test-arg-ds.isNA.R b/tests/testthat/test-arg-ds.isNA.R
index 433857a75..50a2bc9d7 100644
--- a/tests/testthat/test-arg-ds.isNA.R
+++ b/tests/testthat/test-arg-ds.isNA.R
@@ -21,7 +21,7 @@ connect.studies.dataset.cnsim(list("LAB_HDL"))
 
 # context("ds.isNA::arg::errors")
 test_that("isNA errors", {
-    expect_error(ds.isNA(), "Please provide the name of the input vector!", fixed=TRUE)
+    expect_error(ds.isNA(), "must be the name of the input vector", fixed=TRUE)
 })
 
 #
diff --git a/tests/testthat/test-arg-ds.isValid.R b/tests/testthat/test-arg-ds.isValid.R
index 4d97f1fa9..65e81ee41 100644
--- a/tests/testthat/test-arg-ds.isValid.R
+++ b/tests/testthat/test-arg-ds.isValid.R
@@ -21,7 +21,7 @@ connect.studies.dataset.cnsim(list("LAB_HDL"))
 
 # context("ds.isValid::arg::errors")
 test_that("isValid errors", {
-    expect_error(ds.isValid(), "Please provide the name of the input vector!", fixed=TRUE)
+    expect_error(ds.isValid(), "must be the name of the input vector", fixed=TRUE)
 })
 
 #
diff --git a/tests/testthat/test-arg-ds.kurtosis.R b/tests/testthat/test-arg-ds.kurtosis.R
index 0d8118e12..677fb2c55 100644
--- a/tests/testthat/test-arg-ds.kurtosis.R
+++ b/tests/testthat/test-arg-ds.kurtosis.R
@@ -27,10 +27,10 @@ test_that("setup", {
 
 # context("ds.kurtosis::arg::test errors")
 test_that("kurtosis_erros", {
-    expect_error(ds.kurtosis(), "Please provide the name of the input vector!", fixed=TRUE)
-    expect_error(ds.kurtosis(x='D$LAB_TSC', type='datashield'), "Function argument \"type\" has to be either \"both\", \"combine\" or \"split\"", fixed=TRUE)
-    expect_error(ds.kurtosis(x='D$LAB_TSC', method="0"), "method must be an integer between 1 and 3", fixed=TRUE)
-    expect_error(ds.kurtosis(x='D$LAB_TSC', method="4"), "method must be an integer between 1 and 3", fixed=TRUE)
+    expect_error(ds.kurtosis(), "must be the name of the input vector", fixed=TRUE)
+    expect_error(ds.kurtosis(x='D$LAB_TSC', type='datashield'), "must be \"both\", \"combine\", or \"split\"", fixed=TRUE)
+    expect_error(ds.kurtosis(x='D$LAB_TSC', method="0"), "must be an integer between 1 and 3", fixed=TRUE)
+    expect_error(ds.kurtosis(x='D$LAB_TSC', method="4"), "must be an integer between 1 and 3", fixed=TRUE)
 })
 
 #
diff --git a/tests/testthat/test-arg-ds.length.R b/tests/testthat/test-arg-ds.length.R
index 7e997842f..36785af17 100644
--- a/tests/testthat/test-arg-ds.length.R
+++ b/tests/testthat/test-arg-ds.length.R
@@ -21,8 +21,8 @@ connect.studies.dataset.cnsim(list("LAB_TSC"))
 
 # context("ds.length::arg::test errors")
 test_that("length_erros", {
-    expect_error(ds.length(), "Please provide the name of the input object!", fixed=TRUE)
-    expect_error(ds.length(x='D$LAB_TSC', type='datashield'), 'Function argument "type" has to be either "both", "combine" or "split"', fixed=TRUE)
+    expect_error(ds.length(), "must be the name of the input object", fixed=TRUE)
+    expect_error(ds.length(x='D$LAB_TSC', type='datashield'), "must be \"both\", \"combine\", or \"split\"", fixed=TRUE)
 })
 
 #
diff --git a/tests/testthat/test-arg-ds.levels.R b/tests/testthat/test-arg-ds.levels.R
index ad2f5bde1..f35810f05 100644
--- a/tests/testthat/test-arg-ds.levels.R
+++ b/tests/testthat/test-arg-ds.levels.R
@@ -21,7 +21,7 @@ connect.studies.dataset.cnsim(list("LAB_TSC"))
 
 # context("ds.levels::arg")
 test_that("simple levels", {
-    expect_error(ds.levels(), "Please provide the name of the input vector!", fixed=TRUE)
+    expect_error(ds.levels(), "must be the name of the input vector", fixed=TRUE)
 })
 
 #
diff --git a/tests/testthat/test-arg-ds.lexis.R b/tests/testthat/test-arg-ds.lexis.R
index 52d1657df..c0f5ca66d 100644
--- a/tests/testthat/test-arg-ds.lexis.R
+++ b/tests/testthat/test-arg-ds.lexis.R
@@ -21,7 +21,7 @@ connect.studies.dataset.cnsim(list("LAB_TSC"))
 
 # context("ds.lexis::arg::test errors")
 test_that("lexis_erros", {
-    expect_error(ds.lexis(), "Please provide the name of the column that holds the subject IDs!", fixed=TRUE)
+    expect_error(ds.lexis(), "must be the name of the column that holds subject IDs", fixed=TRUE)
 })
 
 # context("ds.lexis::arg::test intervalWidth")
diff --git a/tests/testthat/test-arg-ds.list.R b/tests/testthat/test-arg-ds.list.R
index b2bc229d6..8ef1525b7 100644
--- a/tests/testthat/test-arg-ds.list.R
+++ b/tests/testthat/test-arg-ds.list.R
@@ -21,7 +21,7 @@ connect.studies.dataset.cnsim(list("LAB_TSC"))
 
 # context("ds.list::arg::test errors")
 test_that("simple ds.list errors", {
-    expect_error(ds.list(), "x=NULL. Please provide the names of the objects to coerce into a list!")
+    expect_error(ds.list(), "must be the names of the objects to coerce into a list")
 })
 
 #
diff --git a/tests/testthat/test-arg-ds.lmerSLMA.R b/tests/testthat/test-arg-ds.lmerSLMA.R
index d5f6510da..2b5937535 100644
--- a/tests/testthat/test-arg-ds.lmerSLMA.R
+++ b/tests/testthat/test-arg-ds.lmerSLMA.R
@@ -38,13 +38,10 @@ test_that("simple lmerSLMA tesing (mis)use of arguments", {
     expect_length(errs$sim2, 0)
     expect_length(errs$sim3, 0)
 
-    res <- ds.lmerSLMA(formula = 'incid_rate ~ trtGrp + Male + (1|idDoctor)', dataName = 'D', control_type = 'xtol_rel')
-    expect_equal(res$errorMessage, "ERROR: if control_type is non-null, you must specify a valid control_value eg control_value<-1.0e-7", fixed=TRUE)
-#    res <- ds.lmerSLMA(formula = 'incid_rate ~ trtGrp + Male + (1|idDoctor)', dataName = 'D', control_type = 'xtol_rel',control_value = 'nothing')
-#    expect_equal(res$study1$errorMessage, "REAL() can only be applied to a 'numeric', not a 'logical'", fixed=TRUE)
+    expect_error(ds.lmerSLMA(formula = 'incid_rate ~ trtGrp + Male + (1|idDoctor)', dataName = 'D', control_type = 'xtol_rel'), "must be set when")
 
 
-    expect_error(ds.lmerSLMA(), " Please provide a valid regression formula!", fixed=TRUE)
+    expect_error(ds.lmerSLMA(), "must be a valid regression formula", fixed=TRUE)
 })
 
 #
diff --git a/tests/testthat/test-arg-ds.log.R b/tests/testthat/test-arg-ds.log.R
index b51cdf7d4..167fc0757 100644
--- a/tests/testthat/test-arg-ds.log.R
+++ b/tests/testthat/test-arg-ds.log.R
@@ -21,7 +21,7 @@ connect.studies.dataset.cnsim(list("LAB_TSC"))
 
 # context("ds.log::arg::test errors")
 test_that("log_erros", {
-    expect_error(ds.log(), "Please provide the name of the input vector!", fixed=TRUE)
+    expect_error(ds.log(), "must be the name of the input vector", fixed=TRUE)
 })
 
 #
diff --git a/tests/testthat/test-arg-ds.ls.R b/tests/testthat/test-arg-ds.ls.R
index bf24b112d..f305751d5 100644
--- a/tests/testthat/test-arg-ds.ls.R
+++ b/tests/testthat/test-arg-ds.ls.R
@@ -27,20 +27,11 @@ test_that("setup", {
 
 # context("ds.ls::arg")
 test_that("containing escape sequence", {
-    res1 <- ds.ls(search.filter="_:A:_Environment")
+    expect_error(ds.ls(search.filter="_:A:_Environment"), "also appears")
 
-    expect_length(res1, 1)
-    expect_equal(res1, "Warning: Code replacing wildcard (i.e. '*') is '_:A:_' but this appears in your original search filter string - please respecify")
+    expect_error(ds.ls(search.filter="Envir_:A:_oment"), "also appears")
 
-    res2 <- ds.ls(search.filter="Envir_:A:_oment")
-
-    expect_length(res2, 1)
-    expect_equal(res2, "Warning: Code replacing wildcard (i.e. '*') is '_:A:_' but this appears in your original search filter string - please respecify")
-
-    res3 <- ds.ls(search.filter="Environment_:A:_")
-
-    expect_length(res3, 1)
-    expect_equal(res3, "Warning: Code replacing wildcard (i.e. '*') is '_:A:_' but this appears in your original search filter string - please respecify")
+    expect_error(ds.ls(search.filter="Environment_:A:_"), "also appears")
 })
 
 #
diff --git a/tests/testthat/test-arg-ds.make.R b/tests/testthat/test-arg-ds.make.R
index 170b6f113..c23ee9f8f 100644
--- a/tests/testthat/test-arg-ds.make.R
+++ b/tests/testthat/test-arg-ds.make.R
@@ -21,7 +21,7 @@ connect.studies.dataset.cnsim(list("LAB_TSC"))
 
 # context("ds.make::arg::test errors")
 test_that("make_erros", {
-    expect_error(ds.make(), "Please give the name of object to assign or an expression to evaluate and assign.!\n", fixed=TRUE)
+    expect_error(ds.make(), "must be the name of the object to assign", fixed=TRUE)
 })
 
 #
diff --git a/tests/testthat/test-arg-ds.matrix.R b/tests/testthat/test-arg-ds.matrix.R
index c6cf9089e..ece363542 100644
--- a/tests/testthat/test-arg-ds.matrix.R
+++ b/tests/testthat/test-arg-ds.matrix.R
@@ -21,9 +21,8 @@ connect.studies.dataset.cnsim(list("LAB_TSC"))
 
 # context("ds.matrix::arg::test errors")
 test_that("matrix_erros", {
-    res <- ds.matrix(mdata=NULL)
+    expect_error(ds.matrix(mdata=NULL), "must be a character string, numeric vector or scalar")
 
-    expect_equal(res, "Error: mdata must be a character string, a numeric vector or a scalar")
 })
 
 #
diff --git a/tests/testthat/test-arg-ds.matrixDet.R b/tests/testthat/test-arg-ds.matrixDet.R
index c598d81b7..265a8005f 100644
--- a/tests/testthat/test-arg-ds.matrixDet.R
+++ b/tests/testthat/test-arg-ds.matrixDet.R
@@ -21,9 +21,8 @@ connect.studies.dataset.cnsim(list("LAB_TSC"))
 
 # context("ds.matrixDet::arg::test errors")
 test_that("matrixDet_erros", {
-    res <- ds.matrixDet()
+    expect_error(ds.matrixDet(), "must be the name of the matrix that represents M1")
 
-    expect_equal(res, "Error: Please provide the name of the matrix representing M1")
 })
 
 #
diff --git a/tests/testthat/test-arg-ds.matrixDet.report.R b/tests/testthat/test-arg-ds.matrixDet.report.R
index d76b92392..10d028ced 100644
--- a/tests/testthat/test-arg-ds.matrixDet.report.R
+++ b/tests/testthat/test-arg-ds.matrixDet.report.R
@@ -22,9 +22,8 @@ connect.studies.dataset.cnsim(list("LAB_TSC"))
 # context("ds.matrixDet.report::arg::test errors")
 
 test_that("ds.matixDet.report erros", {
-    res <- ds.matrixDet.report(M1=NULL)
+    expect_error(ds.matrixDet.report(M1=NULL), "must be the name of the matrix that represents M1")
 
-    expect_equal(res, "Error: Please provide the name of the matrix representing M1")
 })
 
 #
diff --git a/tests/testthat/test-arg-ds.matrixDiag.R b/tests/testthat/test-arg-ds.matrixDiag.R
index 0dc152ff2..9003e658a 100644
--- a/tests/testthat/test-arg-ds.matrixDiag.R
+++ b/tests/testthat/test-arg-ds.matrixDiag.R
@@ -21,10 +21,8 @@ connect.studies.dataset.cnsim(list("LAB_TSC"))
 
 # context("ds.matrixDiag::arg::test errors")
 test_that("matrixDiag_erros", {
-    res <- ds.matrixDiag()
+    expect_error(ds.matrixDiag(), "must be a character string, numeric vector or scalar")
 
-    expect_length(res, 1)
-    expect_equal(res, "Error: x1 must have a value which is a character string, a numeric vector or a scalar", fixed=TRUE)
 })
 
 #
diff --git a/tests/testthat/test-arg-ds.matrixDimnames.R b/tests/testthat/test-arg-ds.matrixDimnames.R
index c6da09344..5f149cdbe 100644
--- a/tests/testthat/test-arg-ds.matrixDimnames.R
+++ b/tests/testthat/test-arg-ds.matrixDimnames.R
@@ -21,9 +21,8 @@ connect.studies.dataset.cnsim(list("LAB_TSC"))
 
 # context("ds.matrixDimnames::arg::test errors")
 test_that("matrixDimnames_erros", {
-    res <- ds.matrixDimnames()
+    expect_error(ds.matrixDimnames(), "must be the name of the matrix that represents M1")
 
-    expect_equal(res, "Error: Please provide the name of the matrix representing M1")
 })
 
 #
diff --git a/tests/testthat/test-arg-ds.matrixInvert.R b/tests/testthat/test-arg-ds.matrixInvert.R
index dfed18dd6..afc50a1d5 100644
--- a/tests/testthat/test-arg-ds.matrixInvert.R
+++ b/tests/testthat/test-arg-ds.matrixInvert.R
@@ -21,9 +21,8 @@ connect.studies.dataset.cnsim(list("LAB_TSC"))
 
 # context("ds.matrixInvert::arg::test errors")
 test_that("matrixInvert_erros", {
-    res <- ds.matrixInvert()
+    expect_error(ds.matrixInvert(), "must be the name of the matrix that represents M1")
 
-    expect_equal(res, "Error: Please provide the name of the matrix representing M1")
 })
 
 #
diff --git a/tests/testthat/test-arg-ds.matrixMult.R b/tests/testthat/test-arg-ds.matrixMult.R
index 95564e0d5..9e5274d3d 100644
--- a/tests/testthat/test-arg-ds.matrixMult.R
+++ b/tests/testthat/test-arg-ds.matrixMult.R
@@ -21,9 +21,8 @@ connect.studies.dataset.cnsim(list("LAB_TSC"))
 
 # context("ds.matrixMult::arg::test errors")
 test_that("matrixMult_erros", {
-    res <- ds.matrixMult()
+    expect_error(ds.matrixMult(), "must be the name of the matrix that represents M1")
 
-    expect_equal(res, "Error: Please provide the name of the matrix representing M1")
 })
 
 #
diff --git a/tests/testthat/test-arg-ds.matrixTranspose.R b/tests/testthat/test-arg-ds.matrixTranspose.R
index d78c69041..d9d2e7853 100644
--- a/tests/testthat/test-arg-ds.matrixTranspose.R
+++ b/tests/testthat/test-arg-ds.matrixTranspose.R
@@ -21,9 +21,8 @@ connect.studies.dataset.cnsim(list("LAB_TSC"))
 
 # context("ds.matrixTranspose::arg::test errors")
 test_that("matrixTranspose_erros", {
-    res <- ds.matrixTranspose()
+    expect_error(ds.matrixTranspose(), "must be the name of the matrix that represents M1")
 
-    expect_equal(res, "Error: Please provide the name of the matrix representing M1")
 })
 
 #
diff --git a/tests/testthat/test-arg-ds.mean.R b/tests/testthat/test-arg-ds.mean.R
index 36c365bc5..f99961119 100644
--- a/tests/testthat/test-arg-ds.mean.R
+++ b/tests/testthat/test-arg-ds.mean.R
@@ -21,8 +21,8 @@ connect.studies.dataset.cnsim(list("LAB_TSC"))
 
 # context("ds.mean::arg::test errors")
 test_that("mean_erros", {
-    expect_error(ds.mean(), "Please provide the name of the input object!", fixed=TRUE)
-    expect_error(ds.mean(x='D$LAB_TSC', type='datashield'), 'Function argument "type" has to be either "both", "combine" or "split"', fixed=TRUE)
+    expect_error(ds.mean(), "must be the name of the input object", fixed=TRUE)
+    expect_error(ds.mean(x='D$LAB_TSC', type='datashield'), "must be \"both\", \"combine\", or \"split\"", fixed=TRUE)
 })
 
 #context("ds.mean::arg::discordant errors")
diff --git a/tests/testthat/test-arg-ds.meanSdGp.R b/tests/testthat/test-arg-ds.meanSdGp.R
index bac7b2c46..23db6fde3 100644
--- a/tests/testthat/test-arg-ds.meanSdGp.R
+++ b/tests/testthat/test-arg-ds.meanSdGp.R
@@ -21,7 +21,7 @@ connect.studies.dataset.cnsim(list("LAB_TSC"))
 
 # context("ds.meanSdGp::arg::test errors")
 test_that("meanSdGp_erros", {
-    expect_error(ds.meanSdGp(), "Please provide the name of the input vector!", fixed=TRUE)
+    expect_error(ds.meanSdGp(), "must be the name of the input vector", fixed=TRUE)
 })
 
 #
diff --git a/tests/testthat/test-arg-ds.merge.R b/tests/testthat/test-arg-ds.merge.R
index 03a6967a7..19d3a54c4 100644
--- a/tests/testthat/test-arg-ds.merge.R
+++ b/tests/testthat/test-arg-ds.merge.R
@@ -21,11 +21,11 @@ connect.studies.dataset.cnsim(list("LAB_TSC"))
 
 # context("ds.merge::arg::test errors")
 test_that("merge_erros", {
-    expect_error(ds.merge(), "Please provide the name (eg 'name1') of first dataframe to be merged (called x) ", fixed=TRUE)
-    expect_error(ds.merge(x.name="A"), "Please provide the name (eg 'name2') of second dataframe to be merged (called y) ", fixed=TRUE)
+    expect_error(ds.merge(), "must be the name of the first data.frame to merge", fixed=TRUE)
+    expect_error(ds.merge(x.name="A"), "must be the name of the second data.frame to merge", fixed=TRUE)
     expect_error(ds.merge(x.name="D$LAB_TSC", y.name="B", by.x.names="LAB_TSC", by.y.names="LAB_TSC"), "DataSHIELD errors")
-    expect_error(ds.merge(x.name="D$LAB_TSC", y.name="D$LAB_TSC", by.x.names="C"), "Please provide the names of columns in y dataframe on which to merge (eg c('id', 'time'))", fixed=TRUE)
-    expect_error(ds.merge(x.name="D$LAB_TSC", y.name="D$LAB_TSC", by.x.names="D$LAB_TSC", by.y.names="D", suffixes=NULL), "Please provide the suffixes to append to disambiguate duplicate column names (default = c('.x','.y'))", fixed=TRUE)
+    expect_error(ds.merge(x.name="D$LAB_TSC", y.name="D$LAB_TSC", by.x.names="C"), "must be the names of the columns in y to merge on", fixed=TRUE)
+    expect_error(ds.merge(x.name="D$LAB_TSC", y.name="D$LAB_TSC", by.x.names="D$LAB_TSC", by.y.names="D", suffixes=NULL), "must be the suffixes that separate duplicate column names", fixed=TRUE)
 })
 
 #
diff --git a/tests/testthat/test-arg-ds.mice.R b/tests/testthat/test-arg-ds.mice.R
index a90c9c166..84bf9d7a8 100644
--- a/tests/testthat/test-arg-ds.mice.R
+++ b/tests/testthat/test-arg-ds.mice.R
@@ -21,7 +21,7 @@ connect.studies.dataset.cnsim(list("LAB_TSC"))
 
 # context("ds.mice::arg::test errors")
 test_that("mice_errors", {
-    expect_error(ds.mice(), "Please provide the name of the dataframe or matrix that contains the incomplete data!", fixed=TRUE)
+    expect_error(ds.mice(), "must be the name of the data.frame or matrix", fixed=TRUE)
 })
 
 #
diff --git a/tests/testthat/test-arg-ds.names.R b/tests/testthat/test-arg-ds.names.R
index 3faa397a7..62d72c4ce 100644
--- a/tests/testthat/test-arg-ds.names.R
+++ b/tests/testthat/test-arg-ds.names.R
@@ -21,7 +21,7 @@ connect.studies.dataset.cnsim(list("LAB_TSC"))
 
 # context("ds.names::arg::test errors")
 test_that("simple ds.names errors", {
-    expect_error(ds.names(), "Please provide the name of the input list!", fixed=TRUE)
+    expect_error(ds.names(), "must be the name of the input list", fixed=TRUE)
 
     res.errors <- DSI::datashield.errors()
 
diff --git a/tests/testthat/test-arg-ds.ns.R b/tests/testthat/test-arg-ds.ns.R
index 56fb58f5a..ff83bf883 100644
--- a/tests/testthat/test-arg-ds.ns.R
+++ b/tests/testthat/test-arg-ds.ns.R
@@ -28,7 +28,7 @@ test_that("setup", {
 # context("ds.ns::arg::test errors")
 test_that("ns_errors", {
     expect_error(ds.ns(), "argument \"x\" is missing, with no default", fixed=TRUE)
-    expect_error(ds.qlspline(x=NULL), "Please provide the name of the input variable x!", fixed=TRUE)
+    expect_error(ds.qlspline(x=NULL), "must be the name of the input variable", fixed=TRUE)
 })
 
 #
diff --git a/tests/testthat/test-arg-ds.numNA.R b/tests/testthat/test-arg-ds.numNA.R
index be436303a..bdfd02940 100644
--- a/tests/testthat/test-arg-ds.numNA.R
+++ b/tests/testthat/test-arg-ds.numNA.R
@@ -21,7 +21,7 @@ connect.studies.dataset.cnsim(list("LAB_TSC"))
 
 # context("ds.numNA::arg::test errors")
 test_that("simple ds.numNA errors", {
-    expect_error(ds.numNA(), "Please provide the name of a vector!")
+    expect_error(ds.numNA(), "must be the name of a vector")
 })
 
 #
diff --git a/tests/testthat/test-arg-ds.qlspline.R b/tests/testthat/test-arg-ds.qlspline.R
index c7ff7650a..3dacd636c 100644
--- a/tests/testthat/test-arg-ds.qlspline.R
+++ b/tests/testthat/test-arg-ds.qlspline.R
@@ -28,9 +28,9 @@ test_that("setup", {
 # context("ds.qlspline::arg::test errors")
 test_that("qlspline_errors", {
     expect_error(ds.qlspline(), "argument \"x\" is missing, with no default", fixed=TRUE)
-    expect_error(ds.qlspline(x=NULL), "Please provide the name of the input variable x!", fixed=TRUE)
+    expect_error(ds.qlspline(x=NULL), "must be the name of the input variable", fixed=TRUE)
     expect_error(ds.qlspline(x='D$PM_BMI_CONTINUOUS'), "argument \"q\" is missing, with no default", fixed=TRUE)
-    expect_error(ds.qlspline(x='D$PM_BMI_CONTINUOUS', q=NULL), "Argument 'q' is missing, with no default!", fixed=TRUE)
+    expect_error(ds.qlspline(x='D$PM_BMI_CONTINUOUS', q=NULL), "must be a number of quantiles", fixed=TRUE)
 })
 
 #
diff --git a/tests/testthat/test-arg-ds.quantileMean.R b/tests/testthat/test-arg-ds.quantileMean.R
index ef7784341..e762218a7 100644
--- a/tests/testthat/test-arg-ds.quantileMean.R
+++ b/tests/testthat/test-arg-ds.quantileMean.R
@@ -21,8 +21,8 @@ connect.studies.dataset.cnsim(list('LAB_HDL'))
 
 # context("ds.quantileMean::arg::test errors")
 test_that("quantileMean_erros", {
-    expect_error(ds.quantileMean(), "Please provide the name of the input vector!", fixed=TRUE)
-    expect_error(ds.quantileMean(x='D$LAB_HDL', type='datashield'), 'Function argument "type" has to be either "combine" or "split"', fixed=TRUE)
+    expect_error(ds.quantileMean(), "must be the name of the input vector", fixed=TRUE)
+    expect_error(ds.quantileMean(x='D$LAB_HDL', type='datashield'), "must be \"combine\" or \"split\"", fixed=TRUE)
 })
 
 #
diff --git a/tests/testthat/test-arg-ds.rBinom.R b/tests/testthat/test-arg-ds.rBinom.R
index 8d4100bde..bb5119f05 100644
--- a/tests/testthat/test-arg-ds.rBinom.R
+++ b/tests/testthat/test-arg-ds.rBinom.R
@@ -21,10 +21,7 @@ connect.studies.dataset.cnsim(list("LAB_TSC"))
 
 # context("ds.rBinom::arg::test errors")
 test_that("rBinom_erros", {
-    error.message <- ds.rBinom(seed.as.integer='Value')
-
-    expect_equal(class(error.message), 'character')
-    expect_equal(error.message, 'ERROR failed: seed.as.integer must be set as an integer [numeric] or left NULL')
+    expect_error(ds.rBinom(seed.as.integer='Value'), "must be an integer or")
 })
 
 #
diff --git a/tests/testthat/test-arg-ds.rNorm.R b/tests/testthat/test-arg-ds.rNorm.R
index d4ec8075b..215dfd3b2 100644
--- a/tests/testthat/test-arg-ds.rNorm.R
+++ b/tests/testthat/test-arg-ds.rNorm.R
@@ -21,10 +21,7 @@ connect.studies.dataset.cnsim(list("LAB_TSC"))
 
 # context("ds.rNorm::arg::test errors")
 test_that("rNorm_erros", {
-    error.message <- ds.rNorm(seed.as.integer='Value')
-
-    expect_equal(class(error.message), 'character')
-    expect_equal(error.message, 'ERROR failed: seed.as.integer must be set as an integer [numeric] or left NULL')
+    expect_error(ds.rNorm(seed.as.integer='Value'), "must be an integer or")
 })
 
 #
diff --git a/tests/testthat/test-arg-ds.rPois.R b/tests/testthat/test-arg-ds.rPois.R
index 707ca3813..18177209e 100644
--- a/tests/testthat/test-arg-ds.rPois.R
+++ b/tests/testthat/test-arg-ds.rPois.R
@@ -21,10 +21,7 @@ connect.studies.dataset.cnsim(list("LAB_TSC"))
 
 # context("ds.rPois::arg::test errors")
 test_that("rPois_erros", {
-    error.message <- ds.rPois(seed.as.integer='Value')
-
-    expect_equal(class(error.message), 'character')
-    expect_equal(error.message, 'ERROR failed: seed.as.integer must be set as an integer [numeric] or left NULL')
+    expect_error(ds.rPois(seed.as.integer='Value'), "must be an integer or")
 })
 
 #
diff --git a/tests/testthat/test-arg-ds.rUnif.R b/tests/testthat/test-arg-ds.rUnif.R
index be046e8e5..48f3024a8 100644
--- a/tests/testthat/test-arg-ds.rUnif.R
+++ b/tests/testthat/test-arg-ds.rUnif.R
@@ -21,10 +21,7 @@ connect.studies.dataset.cnsim(list("LAB_TSC"))
 
 # context("ds.rUnif::arg::test errors")
 test_that("rUnif_erros", {
-    error.message <- ds.rUnif(seed.as.integer='Value')
-
-    expect_equal(class(error.message), 'character')
-    expect_equal(error.message, 'ERROR failed: seed.as.integer must be set as an integer [numeric] or left NULL')
+    expect_error(ds.rUnif(seed.as.integer='Value'), "must be an integer or")
 })
 
 #
diff --git a/tests/testthat/test-arg-ds.rbind.R b/tests/testthat/test-arg-ds.rbind.R
index 3a4ed9f27..c7da6de8a 100644
--- a/tests/testthat/test-arg-ds.rbind.R
+++ b/tests/testthat/test-arg-ds.rbind.R
@@ -21,7 +21,7 @@ connect.studies.dataset.cnsim(list("LAB_TSC"))
 
 # context("ds.rbind::arg::test errors")
 test_that("rbind_erros", {
-    expect_error(ds.rbind(), "Please provide a vector of character strings holding the name of the input elements!", fixed=TRUE)
+    expect_error(ds.rbind(), "must be a vector of the names of the input elements", fixed=TRUE)
 })
 
 #
diff --git a/tests/testthat/test-arg-ds.reShape.R b/tests/testthat/test-arg-ds.reShape.R
index ed8e8102b..288f98625 100644
--- a/tests/testthat/test-arg-ds.reShape.R
+++ b/tests/testthat/test-arg-ds.reShape.R
@@ -21,10 +21,10 @@ connect.studies.dataset.cnsim(list("LAB_TSC"))
 
 # context("ds.reShape::arg::test errors")
 test_that("reShape_erros", {
-    expect_error(ds.reShape(), "Please provide the name of the list that holds the input vectors!", fixed=TRUE)
-    expect_error(ds.reShape(data.name="test", sep=TRUE), "'sep' must be a character string", fixed=TRUE)
-    expect_error(ds.reShape(data.name="test", sep=""), "'sep' must be a character string", fixed=TRUE)
-    expect_error(ds.reShape(data.name="test", sep="ts"), "'sep' must be a character string", fixed=TRUE)
+    expect_error(ds.reShape(), "must be the name of the list that holds the input vectors", fixed=TRUE)
+    expect_error(ds.reShape(data.name="test", sep=TRUE), "must be a character string", fixed=TRUE)
+    expect_error(ds.reShape(data.name="test", sep=""), "must be a character string", fixed=TRUE)
+    expect_error(ds.reShape(data.name="test", sep="ts"), "must be a character string", fixed=TRUE)
 })
 
 #
diff --git a/tests/testthat/test-arg-ds.recodeValues.R b/tests/testthat/test-arg-ds.recodeValues.R
index 74a2da507..2bb7fd902 100644
--- a/tests/testthat/test-arg-ds.recodeValues.R
+++ b/tests/testthat/test-arg-ds.recodeValues.R
@@ -21,7 +21,7 @@ connect.studies.dataset.cnsim(list("LAB_TSC"))
 
 # context("ds.recodeValues::arg::test errors")
 test_that("recodeValues_erros", {
-    expect_error(ds.recodeValues(), "Please provide the name of the variable to be recoded: eg 'xxx'", fixed=TRUE)
+    expect_error(ds.recodeValues(), "must be the name of the variable to recode", fixed=TRUE)
     expect_error(ds.recodeValues('D$LAB_TSC'), "Please provide a vector in the 'values2replace.vector' argument specifying\n         the values to be replaced eg c(1,7)", fixed=TRUE)
     expect_error(ds.recodeValues('D$LAB_TSC', values2replace.vector=c(0,1)), "Please ensure that values2replace.vector and new.values.vector have same length and are in the same order", fixed=TRUE)
     expect_error(ds.recodeValues('D$LAB_TSC', values2replace.vector=c(0,1), new.values.vector=c(-10)), "Please ensure that values2replace.vector and new.values.vector have same length and are in the same order", fixed=TRUE)
diff --git a/tests/testthat/test-arg-ds.rep.R b/tests/testthat/test-arg-ds.rep.R
index f9c2ec6ba..0791c2be3 100644
--- a/tests/testthat/test-arg-ds.rep.R
+++ b/tests/testthat/test-arg-ds.rep.R
@@ -24,9 +24,8 @@ connect.studies.dataset.survival(list("survtime", "time.id", "female"))
 # context("ds.rep::arg::test errors")
 
 test_that("ds.rep erros", {
-    res <- ds.rep()
+    expect_error(ds.rep(), "must be a character string, a client-side numeric vector")
 
-    expect_equal(res, "Error: x1 must have a value which is a character string, a numeric vector on the clientside or a scalar", fixed=TRUE)
 })
 
 #
diff --git a/tests/testthat/test-arg-ds.replaceNA.R b/tests/testthat/test-arg-ds.replaceNA.R
index acd8c7b7e..6cff90c4f 100644
--- a/tests/testthat/test-arg-ds.replaceNA.R
+++ b/tests/testthat/test-arg-ds.replaceNA.R
@@ -21,8 +21,8 @@ connect.studies.dataset.cnsim(list("LAB_TSC"))
 
 # context("ds.replaceNA::arg::test errors")
 test_that("simple ds.replaceNA errors", {
-    expect_error(ds.replaceNA(), "Please provide the name of a vector!", fixed=TRUE)
-    expect_error(ds.replaceNA(x="D$LAB_TSC"), "Please provide a list of replacement values!", fixed=TRUE)
+    expect_error(ds.replaceNA(), "must be the name of a vector", fixed=TRUE)
+    expect_error(ds.replaceNA(x="D$LAB_TSC"), "must be a list of replacement values", fixed=TRUE)
 })
 
 #
diff --git a/tests/testthat/test-arg-ds.rm.R b/tests/testthat/test-arg-ds.rm.R
index bb674bca1..22d50b8d5 100644
--- a/tests/testthat/test-arg-ds.rm.R
+++ b/tests/testthat/test-arg-ds.rm.R
@@ -22,7 +22,7 @@ connect.studies.dataset.survival(list("survtime", "time.id", "female"))
 # context("ds.rm::arg::test errors")
 
 test_that("ds.rm erros", {
-    expect_error(ds.rm(), "Please provide the names of the objects to be deleted (eg 'object.name') as the x.names argument", fixed=TRUE)
+    expect_error(ds.rm(), "must be the names of the objects to delete", fixed=TRUE)
 })
 
 #
diff --git a/tests/testthat/test-arg-ds.rowColCalc.R b/tests/testthat/test-arg-ds.rowColCalc.R
index 76b8604bb..a5a473f64 100644
--- a/tests/testthat/test-arg-ds.rowColCalc.R
+++ b/tests/testthat/test-arg-ds.rowColCalc.R
@@ -21,9 +21,9 @@ connect.studies.dataset.cnsim(list("LAB_TSC", "LAB_HDL"))
 
 # context("ds.rowColCalc::arg::test errors")
 test_that("rowColCalc_errors", {
-    expect_error(ds.rowColCalc(), "Please provide the name of a data.frame or matrix!", fixed=TRUE)
+    expect_error(ds.rowColCalc(), "must be the name of a data.frame or matrix", fixed=TRUE)
     expect_error(ds.rowColCalc(x='D', newobj="rsum_hdl_tsc"), "'operation' = NULL. Please set it to 'rowSums', 'colSums', 'rowMeans' or 'colMeans'", fixed=TRUE)
-    expect_error(ds.rowColCalc(x='D', newobj="rsum_hdl_tsc", operation="datashield"), "'operation' must be set to: 'rowSums', 'colSums', 'rowMeans' or 'colMeans'", fixed=TRUE)
+    expect_error(ds.rowColCalc(x='D', newobj="rsum_hdl_tsc", operation="datashield"), "must be \"rowSums\", \"colSums\", \"rowMeans\", or \"colMeans\"", fixed=TRUE)
 })
 
 #
diff --git a/tests/testthat/test-arg-ds.sample.R b/tests/testthat/test-arg-ds.sample.R
index f84f4c3e7..6b19a43bc 100644
--- a/tests/testthat/test-arg-ds.sample.R
+++ b/tests/testthat/test-arg-ds.sample.R
@@ -23,12 +23,9 @@ connect.studies.dataset.cnsim(list("LAB_TSC", "LAB_TRIG"))
 
 # context("ds.sample::arg::test errors")
 test_that("cov_erros", {
-    res1 <- ds.sample()
-    expect_equal(res1, 'Error: x must denote a character string naming the serverside object to be sampled or an integer N denoting permute 1:N', fixed=TRUE)
-    res2 <- ds.sample(x='D$LAB_TSC')
-    expect_equal(res2, 'Error: size must have a value which is an integer denoting how many records to be sampled', fixed=TRUE)
-    res3 <- ds.sample(x='D$LAB_TSC', size=1234, seed.as.integer="FooBar")
-    expect_equal(res3, 'ERROR failed: seed.as.integer must be set as an integer [numeric] or left NULL', fixed=TRUE)
+    expect_error(ds.sample(), "must be a character string that names a server-side object")
+    expect_error(ds.sample(x='D$LAB_TSC'), "must be an integer that sets how many records")
+    expect_error(ds.sample(x='D$LAB_TSC', size=1234, seed.as.integer="FooBar"), "must be an integer or")
 })
 
 #
diff --git a/tests/testthat/test-arg-ds.setSeed.R b/tests/testthat/test-arg-ds.setSeed.R
index 1bf41b5ca..4d5010409 100644
--- a/tests/testthat/test-arg-ds.setSeed.R
+++ b/tests/testthat/test-arg-ds.setSeed.R
@@ -21,9 +21,8 @@ connect.studies.dataset.cnsim(list("LAB_TSC"))
 
 # context("ds.setSeed::arg::test errors")
 test_that("setSeed_erros", {
-    res <- ds.setSeed(seed.as.integer="Test")
+    expect_error(ds.setSeed(seed.as.integer="Test"), "must be an integer or")
 
-    expect_equal(res, "ERROR terminated: seed.as.integer must be set as an integer [numeric] or as being NULL")
 })
 
 #
diff --git a/tests/testthat/test-arg-ds.skewness.R b/tests/testthat/test-arg-ds.skewness.R
index 6a9440cc7..070d551d6 100644
--- a/tests/testthat/test-arg-ds.skewness.R
+++ b/tests/testthat/test-arg-ds.skewness.R
@@ -27,10 +27,10 @@ test_that("setup", {
 
 # context("ds.skewness::arg::test errors")
 test_that("skewness_erros", {
-    expect_error(ds.skewness(), "Please provide the name of the input vector!", fixed=TRUE)
-    expect_error(ds.skewness(x='D$LAB_TSC', type='datashield'), "Function argument \"type\" has to be either \"both\", \"combine\" or \"split\"", fixed=TRUE)
-    expect_error(ds.skewness(x='D$LAB_TSC', method="0"), "method must be an integer between 1 and 3", fixed=TRUE)
-    expect_error(ds.skewness(x='D$LAB_TSC', method="4"), "method must be an integer between 1 and 3", fixed=TRUE)
+    expect_error(ds.skewness(), "must be the name of the input vector", fixed=TRUE)
+    expect_error(ds.skewness(x='D$LAB_TSC', type='datashield'), "must be \"both\", \"combine\", or \"split\"", fixed=TRUE)
+    expect_error(ds.skewness(x='D$LAB_TSC', method="0"), "must be an integer between 1 and 3", fixed=TRUE)
+    expect_error(ds.skewness(x='D$LAB_TSC', method="4"), "must be an integer between 1 and 3", fixed=TRUE)
 })
 
 #
diff --git a/tests/testthat/test-arg-ds.sqrt.R b/tests/testthat/test-arg-ds.sqrt.R
index ce4248649..5905864c2 100644
--- a/tests/testthat/test-arg-ds.sqrt.R
+++ b/tests/testthat/test-arg-ds.sqrt.R
@@ -10,7 +10,7 @@ connect.studies.dataset.cnsim(list("LAB_TSC"))
 
 # context("ds.sqrt::arg::test errors")
 test_that("sqrt_errors", {
-    expect_error(ds.sqrt(), "Please provide the name of the input object!", fixed=TRUE)
+    expect_error(ds.sqrt(), "must be the name of the input object", fixed=TRUE)
 })
 
 #
diff --git a/tests/testthat/test-arg-ds.summary.R b/tests/testthat/test-arg-ds.summary.R
index e3d386568..78158c33c 100644
--- a/tests/testthat/test-arg-ds.summary.R
+++ b/tests/testthat/test-arg-ds.summary.R
@@ -21,7 +21,7 @@ connect.studies.dataset.cnsim(list("LAB_TSC"))
 
 # context("ds.summary::arg::test errors")
 test_that("summary_erros", {
-    expect_error(ds.summary(), "Please provide the name of the input vector!", fixed=TRUE)
+    expect_error(ds.summary(), "must be the name of the input vector", fixed=TRUE)
 })
 
 #
diff --git a/tests/testthat/test-arg-ds.table.R b/tests/testthat/test-arg-ds.table.R
index ae781fe20..eaf9b3267 100644
--- a/tests/testthat/test-arg-ds.table.R
+++ b/tests/testthat/test-arg-ds.table.R
@@ -21,33 +21,30 @@ connect.studies.dataset.cnsim(list("DIS_CVA", "DIS_AMI", "LAB_TSC", "LAB_HDL"))
 
 # context("ds.table::arg::test rvar has value")
 test_that("table rvar has value", {
-    res <- ds.table()
+    expect_error(ds.table(), "must be a character string that names the row variable")
     
-    expect_equal(res, "Error: rvar must have a value which is a character string naming the row variable for the table", fixed=TRUE)
 })
 
 # context("ds.table::arg::test cvar has value")
 test_that("table cvar has value", {
-  res <- ds.table(rvar="D$LAB_TSC", cvar=30)
+  expect_error(ds.table(rvar="D$LAB_TSC", cvar=30), "must be a character string that names the column variable")
   
-  expect_equal(res, "Error: if cvar is not null, it must have a value which is a character string naming the column variable for the table", fixed=TRUE)
 })
 
 # context("ds.table::arg::test stvar has value")
 test_that("table stvar has value", {
-  res <- ds.table(rvar="D$LAB_TSC", cvar=NULL, stvar=25)
+  expect_error(ds.table(rvar="D$LAB_TSC", cvar=NULL, stvar=25), "must be a character string that names the variable")
   
-  expect_equal(res, "Error: if stvar is not null, it must have a value which is a character string naming the variable coding separate tables for the table", fixed=TRUE)
 })
 
 # context("ds.table::arg::test stvar has CORRECT value")
 test_that("table useNA has value", {
-  expect_error(ds.table(rvar="D$LAB_TSC", cvar=NULL, stvar=NULL, useNA = c("BEN")), "useNA must be either 'no' or 'always'.", fixed = TRUE)
+  expect_error(ds.table(rvar="D$LAB_TSC", cvar=NULL, stvar=NULL, useNA = c("BEN")), "must be \"no\" or \"always\"", fixed = TRUE)
 })
 
 # context("ds.table::arg::test force.nfilter has value")
 test_that("table force.nfilter has value", {
-  expect_error(ds.table(rvar="D$LAB_TSC", cvar=NULL, stvar=NULL, useNA = c("ifany"), force.nfilter =30), "useNA must be either 'no' or 'always'.", fixed = TRUE)
+  expect_error(ds.table(rvar="D$LAB_TSC", cvar=NULL, stvar=NULL, useNA = c("ifany"), force.nfilter =30), "must be \"no\" or \"always\"", fixed = TRUE)
 })
 
 
diff --git a/tests/testthat/test-arg-ds.tapply.R b/tests/testthat/test-arg-ds.tapply.R
index 5ac42edf5..2bbca9ad2 100644
--- a/tests/testthat/test-arg-ds.tapply.R
+++ b/tests/testthat/test-arg-ds.tapply.R
@@ -21,22 +21,14 @@ connect.studies.dataset.cnsim(list("LAB_TSC", "GENDER"))
 
 # context("ds.tapply::arg::test errors")
 test_that("tapply_erros", {
-    res1 <- ds.tapply()
+    expect_error(ds.tapply(), "must be the name of the variable to summarise")
 
-    expect_length(res1, 1)
-    expect_equal(res1, "Error: Please provide the name of the variable to be summarized, as a character string")
 
-    res2 <- ds.tapply('D$LAB_TSC')
+    expect_error(ds.tapply('D$LAB_TSC'), "must name a single factor or a list of factors")
 
-    expect_length(res2, 3)
-    expect_equal(res2$Error.message, "Error: Please provide the name of the single factor or")
-    expect_equal(res2$Err.cont2, "the list of factors to index the variable to be summarized.")
-    expect_equal(res2$Err.cont3, "In either case the argument must be specified in inverted commas")
 
-    res3 <- ds.tapply('D$LAB_TSC', 'D$GENDER')
+    expect_error(ds.tapply('D$LAB_TSC', 'D$GENDER'), "must be a valid summarising function")
 
-    expect_length(res3, 1)
-    expect_equal(res3, "Error: Please provide a valid summarizing function, as a character string")
 })
 
 #
diff --git a/tests/testthat/test-arg-ds.tapply.assign.R b/tests/testthat/test-arg-ds.tapply.assign.R
index 14ea83890..b14bad48e 100644
--- a/tests/testthat/test-arg-ds.tapply.assign.R
+++ b/tests/testthat/test-arg-ds.tapply.assign.R
@@ -21,22 +21,14 @@ connect.studies.dataset.cnsim(list("LAB_TSC", "GENDER"))
 
 # context("ds.tapply.assign::arg::test errors")
 test_that("tapply_erros", {
-    res1 <- ds.tapply.assign()
+    expect_error(ds.tapply.assign(), "must be the name of the variable to summarise")
 
-    expect_length(res1, 1)
-    expect_equal(res1, "Error: Please provide the name of the variable to be summarized, as a character string")
 
-    res2 <- ds.tapply.assign('D$LAB_TSC')
+    expect_error(ds.tapply.assign('D$LAB_TSC'), "must name a single factor or a list of factors")
 
-    expect_length(res2, 3)
-    expect_equal(res2$Error.message, "Error: Please provide the name of the single factor or")
-    expect_equal(res2$Err.cont2, "the list of factors to index the variable to be summarized.")
-    expect_equal(res2$Err.cont3, "In either case the argument must be specified in inverted commas")
 
-    res3 <- ds.tapply.assign('D$LAB_TSC', 'D$GENDER')
+    expect_error(ds.tapply.assign('D$LAB_TSC', 'D$GENDER'), "must be a valid summarising function")
 
-    expect_length(res3, 1)
-    expect_equal(res3, "Error: Please provide a valid summarizing function, as a character string")
 })
 
 #
diff --git a/tests/testthat/test-arg-ds.unList.R b/tests/testthat/test-arg-ds.unList.R
index 2d3aa4877..9016b05cd 100644
--- a/tests/testthat/test-arg-ds.unList.R
+++ b/tests/testthat/test-arg-ds.unList.R
@@ -21,7 +21,7 @@ connect.studies.dataset.cnsim(list("LAB_TSC"))
 
 # context("ds.unList::arg::test errors")
 test_that("unList_erros", {
-    expect_error(ds.unList(), "Please provide the name of the input vector!", fixed=TRUE)
+    expect_error(ds.unList(), "must be the name of the input vector", fixed=TRUE)
 })
 
 #
diff --git a/tests/testthat/test-arg-ds.unique.R b/tests/testthat/test-arg-ds.unique.R
index a0e112a59..ba207f717 100644
--- a/tests/testthat/test-arg-ds.unique.R
+++ b/tests/testthat/test-arg-ds.unique.R
@@ -21,12 +21,12 @@ connect.studies.dataset.cnsim(list("LAB_TSC"))
 
 # context("ds.unique::arg::no arguments")
 test_that("simple ds.unique no arguments", {
-    expect_error(ds.unique(), "x.name=NULL. Please provide the names of the objects to de-duplicated!", fixed = TRUE)
+    expect_error(ds.unique(), "must be the names of the objects to de-duplicate", fixed = TRUE)
 })
 
 # context("ds.unique::arg::NULL arguments")
 test_that("simple ds.unique NULL arguments", {
-    expect_error(ds.unique(NULL), "x.name=NULL. Please provide the names of the objects to de-duplicated!", fixed = TRUE)
+    expect_error(ds.unique(NULL), "must be the names of the objects to de-duplicate", fixed = TRUE)
 })
 
 #
diff --git a/tests/testthat/test-arg-ds.var.R b/tests/testthat/test-arg-ds.var.R
index e745cbcfc..27ab699a1 100644
--- a/tests/testthat/test-arg-ds.var.R
+++ b/tests/testthat/test-arg-ds.var.R
@@ -21,7 +21,7 @@ connect.studies.dataset.cnsim(list("LAB_TSC"))
 
 # context("ds.var::arg::test errors")
 test_that("var_erros", {
-    expect_error(ds.var(), "Please provide the name of the input object!", fixed=TRUE)
+    expect_error(ds.var(), "must be the name of the input object", fixed=TRUE)
 })
 
 #
diff --git a/tests/testthat/test-arg-per-study-arguments.R b/tests/testthat/test-arg-per-study-arguments.R
index 26a79582f..afea544d1 100644
--- a/tests/testthat/test-arg-per-study-arguments.R
+++ b/tests/testthat/test-arg-per-study-arguments.R
@@ -37,8 +37,8 @@ test_that(".expandToStudies keeps one value per study", {
 })
 
 test_that(".expandToStudies rejects any other length", {
-    expect_error(.expandToStudies(c(1, 2), "x", 3), "'x' must be length 1 or one value per\\s+study")
-    expect_error(.expandToStudies(c(1, 2, 3, 4), "x", 3), "'x' must be length 1 or one value per\\s+study")
+    expect_error(.expandToStudies(c(1, 2), "x", 3), "must have length 1")
+    expect_error(.expandToStudies(c(1, 2, 3, 4), "x", 3), "must have length 1")
 })
 
 # context("per-study arguments::arg::ds.rBinom")
@@ -65,16 +65,15 @@ test_that("ds.rBinom sends a single size and prob to every study", {
 test_that("ds.rBinom rejects size or prob with the wrong number of values", {
     sent <- record_server_calls()
 
-    expect_error(ds.rBinom(samp.size = 10, size = c(1, 10), prob = 0.5, newobj = "x", seed.as.integer = 27, datasources = studies), "'size' must be length 1 or one value per\\s+study")
-    expect_error(ds.rBinom(samp.size = 10, size = 5, prob = c(0.1, 0.5), newobj = "x", seed.as.integer = 27, datasources = studies), "'prob' must be length 1 or one value per\\s+study")
+    expect_error(ds.rBinom(samp.size = 10, size = c(1, 10), prob = 0.5, newobj = "x", seed.as.integer = 27, datasources = studies), "must have length 1")
+    expect_error(ds.rBinom(samp.size = 10, size = 5, prob = c(0.1, 0.5), newobj = "x", seed.as.integer = 27, datasources = studies), "must have length 1")
     expect_length(sent$calls, 0)
 })
 
 test_that("ds.rBinom checks every study's prob", {
     sent <- record_server_calls()
-    res <- ds.rBinom(samp.size = 10, size = 5, prob = c(0.5, 1.5, 0.5), newobj = "x", seed.as.integer = 27, datasources = studies)
+    expect_error(ds.rBinom(samp.size = 10, size = 5, prob = c(0.5, 1.5, 0.5), newobj = "x", seed.as.integer = 27, datasources = studies), "must be between 0 and 1")
 
-    expect_equal(res, "ERROR: prob must lie in range 0 < prob < 1")
     expect_length(sent$calls, 0)
 })
 
@@ -112,17 +111,16 @@ test_that("ds.rNorm sends a single mean, sd and decimal places to every study",
 test_that("ds.rNorm rejects mean, sd or decimal places with the wrong number of values", {
     sent <- record_server_calls()
 
-    expect_error(ds.rNorm(samp.size = 10, mean = c(0, 100), sd = 1, newobj = "x", seed.as.integer = 27, datasources = studies), "'mean' must be length 1 or one value per\\s+study")
-    expect_error(ds.rNorm(samp.size = 10, mean = 0, sd = c(1, 2), newobj = "x", seed.as.integer = 27, datasources = studies), "'sd' must be length 1 or one value per\\s+study")
-    expect_error(ds.rNorm(samp.size = 10, mean = 0, sd = 1, force.output.to.k.decimal.places = c(2, 4), newobj = "x", seed.as.integer = 27, datasources = studies), "'force.output.to.k.decimal.places' must be length 1 or one value per\\s+study")
+    expect_error(ds.rNorm(samp.size = 10, mean = c(0, 100), sd = 1, newobj = "x", seed.as.integer = 27, datasources = studies), "must have length 1")
+    expect_error(ds.rNorm(samp.size = 10, mean = 0, sd = c(1, 2), newobj = "x", seed.as.integer = 27, datasources = studies), "must have length 1")
+    expect_error(ds.rNorm(samp.size = 10, mean = 0, sd = 1, force.output.to.k.decimal.places = c(2, 4), newobj = "x", seed.as.integer = 27, datasources = studies), "must have length 1")
     expect_length(sent$calls, 0)
 })
 
 test_that("ds.rNorm checks every study's sd", {
     sent <- record_server_calls()
-    res <- ds.rNorm(samp.size = 10, mean = 0, sd = c(1, -1, 1), newobj = "x", seed.as.integer = 27, datasources = studies)
+    expect_error(ds.rNorm(samp.size = 10, mean = 0, sd = c(1, -1, 1), newobj = "x", seed.as.integer = 27, datasources = studies), "must be greater than 0")
 
-    expect_equal(res, "ERROR: sd must be > 0")
     expect_length(sent$calls, 0)
 })
 
@@ -150,15 +148,14 @@ test_that("ds.rPois sends a single lambda to every study", {
 test_that("ds.rPois rejects lambda with the wrong number of values", {
     sent <- record_server_calls()
 
-    expect_error(ds.rPois(samp.size = 10, lambda = c(1, 50), newobj = "x", seed.as.integer = 27, datasources = studies), "'lambda' must be length 1 or one value per\\s+study")
+    expect_error(ds.rPois(samp.size = 10, lambda = c(1, 50), newobj = "x", seed.as.integer = 27, datasources = studies), "must have length 1")
     expect_length(sent$calls, 0)
 })
 
 test_that("ds.rPois checks every study's lambda", {
     sent <- record_server_calls()
-    res <- ds.rPois(samp.size = 10, lambda = c(1, 0, 1), newobj = "x", seed.as.integer = 27, datasources = studies)
+    expect_error(ds.rPois(samp.size = 10, lambda = c(1, 0, 1), newobj = "x", seed.as.integer = 27, datasources = studies), "must be greater than 0")
 
-    expect_equal(res, "ERROR: lambda must be > 0")
     expect_length(sent$calls, 0)
 })
 
@@ -186,17 +183,16 @@ test_that("ds.rUnif sends a single min, max and decimal places to every study",
 test_that("ds.rUnif rejects min, max or decimal places with the wrong number of values", {
     sent <- record_server_calls()
 
-    expect_error(ds.rUnif(samp.size = 10, min = c(0, 2), max = 10, newobj = "x", seed.as.integer = 27, datasources = studies), "'min' must be length 1 or one value per\\s+study")
-    expect_error(ds.rUnif(samp.size = 10, min = 0, max = c(2, 5), newobj = "x", seed.as.integer = 27, datasources = studies), "'max' must be length 1 or one value per\\s+study")
-    expect_error(ds.rUnif(samp.size = 10, min = 0, max = 1, force.output.to.k.decimal.places = c(1, 2), newobj = "x", seed.as.integer = 27, datasources = studies), "'force.output.to.k.decimal.places' must be length 1 or one value per\\s+study")
+    expect_error(ds.rUnif(samp.size = 10, min = c(0, 2), max = 10, newobj = "x", seed.as.integer = 27, datasources = studies), "must have length 1")
+    expect_error(ds.rUnif(samp.size = 10, min = 0, max = c(2, 5), newobj = "x", seed.as.integer = 27, datasources = studies), "must have length 1")
+    expect_error(ds.rUnif(samp.size = 10, min = 0, max = 1, force.output.to.k.decimal.places = c(1, 2), newobj = "x", seed.as.integer = 27, datasources = studies), "must have length 1")
     expect_length(sent$calls, 0)
 })
 
 test_that("ds.rUnif checks every study's min and max", {
     sent <- record_server_calls()
-    res <- ds.rUnif(samp.size = 10, min = c(0, 5, 0), max = c(1, 2, 1), newobj = "x", seed.as.integer = 27, datasources = studies)
+    expect_error(ds.rUnif(samp.size = 10, min = c(0, 5, 0), max = c(1, 2, 1), newobj = "x", seed.as.integer = 27, datasources = studies), "must be greater than")
 
-    expect_equal(res, "ERROR: max must be greater than min")
     expect_length(sent$calls, 0)
 })
 
diff --git a/tests/testthat/test-disc-ds.table.R b/tests/testthat/test-disc-ds.table.R
index b51a75f91..b60b6b935 100644
--- a/tests/testthat/test-disc-ds.table.R
+++ b/tests/testthat/test-disc-ds.table.R
@@ -98,15 +98,8 @@ test_that("setup", {
 
 # context("ds.table::disc::tests::phase 2::table.assign=FALSE")
 test_that("table disclosure, table.assign=FALSE", {
-  table.res <- ds.table(rvar='D$GENDER', cvar="D$DIS_AMI", table.assign=FALSE, newobj="new_table3")
-  
-  expect_length(table.res, 2)
-  expect_length(table.res$validity.message, 1)
-  expect_equal(table.res$validity.message, "All studies failed for reasons identified below", fixed = TRUE)
-  expect_length(table.res$error.message, 3)
-  expect_equal(table.res$error.message$sim1, "Failed: at least one cell has a non-zero count less than nfilter.tab i.e. 3", fixed = TRUE)
-  expect_equal(table.res$error.message$sim2, "Failed: at least one cell has a non-zero count less than nfilter.tab i.e. 3", fixed = TRUE)
-  expect_equal(table.res$error.message$sim3, "Failed: at least one cell has a non-zero count less than nfilter.tab i.e. 3", fixed = TRUE)
+  error <- expect_error(ds.table(rvar='D$GENDER', cvar="D$DIS_AMI", table.assign=FALSE, newobj="new_table3"), "All studies failed")
+  expect_match(conditionMessage(error), "non-zero count less than nfilter.tab")
 })
 
 # context("ds.table::disc::tests::phase 2::table.assign=TRUE")
diff --git a/tests/testthat/test-smk-ds.lmerSLMA.R b/tests/testthat/test-smk-ds.lmerSLMA.R
index 620abc63c..63943d39e 100644
--- a/tests/testthat/test-smk-ds.lmerSLMA.R
+++ b/tests/testthat/test-smk-ds.lmerSLMA.R
@@ -51,8 +51,7 @@ test_that("alternative formulae for nested groups", {
 test_that("server side error", {
     res = ds.lmerSLMA(formula = 'BMI ~ trtGrp + Male + (1|idSurgery)', dataName = 'D', optimizer = 'nloptwrap')
     expect_equal(res$Convergence.error.message[2], "Study2: no convergence error reported")
-    res=ds.lmerSLMA(formula = 'BMI ~ trtGrp + Male + (1|idSurgery)', dataName = 'D', optimizer = 'not_this_one')
-    expect_equal(res$errorMessage, "ERROR: the only optimizer currently available for lmer is 'nloptwrap', please respecify")
+    expect_error(ds.lmerSLMA(formula = 'BMI ~ trtGrp + Male + (1|idSurgery)', dataName = 'D', optimizer = 'not_this_one'), "must be \"nloptwrap\"")
     res = ds.lmerSLMA(formula = 'BMI ~ trtGrp + Male + (1|idDoctor)', dataName = "D", REML = FALSE)
     expect_equal(res$output.summary$study1$methTitle, "Linear mixed model fit by maximum likelihood ")
 })
diff --git a/tests/testthat/test-smk-ds.mdPattern.R b/tests/testthat/test-smk-ds.mdPattern.R
index 077012c34..570068458 100644
--- a/tests/testthat/test-smk-ds.mdPattern.R
+++ b/tests/testthat/test-smk-ds.mdPattern.R
@@ -90,7 +90,7 @@ test_that("class consistency check aborts when classes differ across studies", {
     ds.asDataMatrix(x.name = "D", newobj = "mixed.class", datasources = ds.test_env$connections[1])
     ds.assign(toAssign = "D", newobj = "mixed.class", datasources = ds.test_env$connections[2:3])
 
-    expect_error(ds.mdPattern(x = "mixed.class"), "not of the same class in all studies")
+    expect_error(ds.mdPattern(x = "mixed.class"), "must have the same class in all studies")
     expect_no_error(ds.mdPattern(x = "mixed.class", classConsistencyCheck = FALSE))
 })
 
diff --git a/tests/testthat/test-smk-ds.rBinom.R b/tests/testthat/test-smk-ds.rBinom.R
index 3fecc749f..5f3f14ab6 100644
--- a/tests/testthat/test-smk-ds.rBinom.R
+++ b/tests/testthat/test-smk-ds.rBinom.R
@@ -64,7 +64,7 @@ test_that("one value per study", {
 
 # context("ds.rBinom::smk::wrong number of values")
 test_that("wrong number of values per study", {
-    expect_error(ds.rBinom(samp.size = 50, size = c(1, 10), prob = 0.5, newobj = "no.obj", seed.as.integer = 27), "must be length 1 or one value per study")
+    expect_error(ds.rBinom(samp.size = 50, size = c(1, 10), prob = 0.5, newobj = "no.obj", seed.as.integer = 27), "must have length 1")
 })
 
 #
diff --git a/tests/testthat/test-smk-ds.rNorm.R b/tests/testthat/test-smk-ds.rNorm.R
index 1a08b928a..b12f95080 100644
--- a/tests/testthat/test-smk-ds.rNorm.R
+++ b/tests/testthat/test-smk-ds.rNorm.R
@@ -64,7 +64,7 @@ test_that("one value per study", {
 
 # context("ds.rNorm::smk::wrong number of values")
 test_that("wrong number of values per study", {
-    expect_error(ds.rNorm(samp.size = 50, mean = c(0, 100), sd = 1, newobj = "no.obj", seed.as.integer = 27), "must be length 1 or one value per study")
+    expect_error(ds.rNorm(samp.size = 50, mean = c(0, 100), sd = 1, newobj = "no.obj", seed.as.integer = 27), "must have length 1")
 })
 
 #
diff --git a/tests/testthat/test-smk-ds.rPois.R b/tests/testthat/test-smk-ds.rPois.R
index 31baf262d..7ad6fad39 100644
--- a/tests/testthat/test-smk-ds.rPois.R
+++ b/tests/testthat/test-smk-ds.rPois.R
@@ -64,7 +64,7 @@ test_that("one value per study", {
 
 # context("ds.rPois::smk::wrong number of values")
 test_that("wrong number of values per study", {
-    expect_error(ds.rPois(samp.size = 50, lambda = c(1, 50), newobj = "no.obj", seed.as.integer = 27), "must be length 1 or one value per study")
+    expect_error(ds.rPois(samp.size = 50, lambda = c(1, 50), newobj = "no.obj", seed.as.integer = 27), "must have length 1")
 })
 
 #
diff --git a/tests/testthat/test-smk-ds.rUnif.R b/tests/testthat/test-smk-ds.rUnif.R
index a296dfeeb..80ff2442a 100644
--- a/tests/testthat/test-smk-ds.rUnif.R
+++ b/tests/testthat/test-smk-ds.rUnif.R
@@ -64,7 +64,7 @@ test_that("one value per study", {
 
 # context("ds.rUnif::smk::wrong number of values")
 test_that("wrong number of values per study", {
-    expect_error(ds.rUnif(samp.size = 50, min = c(0, 10), max = 30, newobj = "no.obj", seed.as.integer = 27), "must be length 1 or one value per study")
+    expect_error(ds.rUnif(samp.size = 50, min = c(0, 10), max = 30, newobj = "no.obj", seed.as.integer = 27), "must have length 1")
 })
 
 #
diff --git a/tests/testthat/test-utils.R b/tests/testthat/test-utils.R
deleted file mode 100644
index ba0904104..000000000
--- a/tests/testthat/test-utils.R
+++ /dev/null
@@ -1,14 +0,0 @@
-#
-# Tests
-#
-
-# context("utils::.resolveNewobjName")
-test_that(".resolveNewobjName applies the default before validating", {
-    expect_equal(.resolveNewobjName(NULL, "x.newobj"), "x.newobj")
-    expect_equal(.resolveNewobjName("my.obj", "x.newobj"), "my.obj")
-})
-
-test_that(".resolveNewobjName rejects anything but a single character string", {
-    expect_error(.resolveNewobjName(23, "x.newobj"), "'newobj' must be a single character string")
-    expect_error(.resolveNewobjName(c("a", "b"), "x.newobj"), "'newobj' must be a single character string")
-})