pretest for more interpretable error messages

ripley · ripley · commit b2cd771f6b45 · 2025-02-21T16:39:43.000Z
git-svn-id: https://svn.r-project.org/R/trunk@87786 00db46b3-68df-0310-9c12-caf00c1e9a41
diff --git a/src/library/base/R/unlist.R b/src/library/base/R/unlist.R
@@ -1,7 +1,7 @@
 #  File src/library/base/R/unlist.R
 #  Part of the R package, https://www.R-project.org
 #
-#  Copyright (C) 1995-2018 The R Core Team
+#  Copyright (C) 1995-2025 The R Core Team
 #
 #  This program is free software; you can redistribute it and/or modify
 #  it under the terms of the GNU General Public License as published by
@@ -18,6 +18,8 @@
 
 unlist <- function(x, recursive=TRUE, use.names=TRUE)
 {
+    ## for better error messages (islistfactor is not viisble)
+    if(length(recursive) > 1L) stop("'recursive' must be of length 1")
     if(.Internal(islistfactor(x, recursive))) {
         URapply <-
             if(recursive) # use rapply()

Original file line number	Diff line number	Diff line change
`@@ -1,7 +1,7 @@`
`1`	`1`	`# File src/library/base/R/unlist.R`
`2`	`2`	`# Part of the R package, https://www.R-project.org`
`3`	`3`	`#`
`4`		`-# Copyright (C) 1995-2018 The R Core Team`
	`4`	`+# Copyright (C) 1995-2025 The R Core Team`
`5`	`5`	`#`
`6`	`6`	`# This program is free software; you can redistribute it and/or modify`
`7`	`7`	`# it under the terms of the GNU General Public License as published by`
`@@ -18,6 +18,8 @@`
`18`	`18`
`19`	`19`	`unlist <- function(x, recursive=TRUE, use.names=TRUE)`
`20`	`20`	`{`
	`21`	`+ ## for better error messages (islistfactor is not viisble)`
	`22`	`+ if(length(recursive) > 1L) stop("'recursive' must be of length 1")`
`21`	`23`	`if(.Internal(islistfactor(x, recursive))) {`
`22`	`24`	`URapply <-`
`23`	`25`	`if(recursive) # use rapply()`