source() and example() get catch.abort=FALSE; originating from Luke T…

…ierney

git-svn-id: https://svn.r-project.org/R/trunk@85268 00db46b3-68df-0310-9c12-caf00c1e9a41

doc/NEWS.Rd

@@ -177,6 +177,10 @@
       \item The matrix multiplication functions \code{crossprod()} and
       \code{tcrossprod()} are now also primitive and S3 generic, as
       \code{\%*\%} had become in \R 4.3.0.
+
+      \item \code{source()} and \code{example()} get a new optional argument
+      \code{catch.aborts} which allows continued evaluation of the \R code
+      after an error.
     }
   }
 

src/library/base/R/source.R

@@ -24,6 +24,7 @@ function(file, local = FALSE, echo = verbose, print.eval = echo,
 	 max.deparse.length = 150, width.cutoff = 60L,
          deparseCtrl = "showAttributes", ## rather?  c("keepInteger", "showAttributes", "keepNA"),
          chdir = FALSE,
+         catch.aborts = FALSE,
          encoding = getOption("encoding"),
          continue.echo = getOption("continue"),
          skip.echo = 0, keep.source = getOption("keep.source"))
@@ -222,7 +223,11 @@ function(file, local = FALSE, echo = verbose, print.eval = echo,
 	    }
 	}
 	if (!tail) {
-	    yy <- withVisible(eval(ei, envir))
+	    yy <- if(catch.aborts)
+		      withRestarts(
+			  withVisible(eval(ei, envir)),
+			  abort = function() list(value = NULL, visible = FALSE))
+		  else withVisible(eval(ei, envir))
 	    i.symbol <- mode(ei[[1L]]) == "name"
 	    if (!i.symbol) {
 		## ei[[1L]] : the function "<-" or other

src/library/base/man/source.Rd

@@ -27,6 +27,7 @@ source(file, local = FALSE, echo = verbose, print.eval = echo,
        max.deparse.length = 150, width.cutoff = 60L,
        deparseCtrl = "showAttributes",
        chdir = FALSE,
+       catch.aborts = FALSE,
        encoding = getOption("encoding"),
        continue.echo = getOption("continue"),
        skip.echo = 0, keep.source = getOption("keep.source"))
@@ -84,6 +85,8 @@ withAutoprint(exprs, evaluated = FALSE, local = parent.frame(),
   \item{chdir}{logical; if \code{TRUE} and \code{file} is a pathname,
     the \R working directory is temporarily changed to the directory
     containing \code{file} for evaluating.}
+  \item{catch.aborts}{logical indicating that \dQuote{abort}ing errors
+    should be caught.}
   \item{encoding}{character vector.  The encoding(s) to be assumed when
     \code{file} is a character string: see \code{\link{file}}.  A
     possible value is \code{"unknown"} when the encoding is guessed: see
@@ -191,7 +194,7 @@ if(someCond) withAutoprint({
 ## If you want to source() a bunch of files, something like
 ## the following may be useful:
 sourceDir <- function(path, trace = TRUE, ...) {
-    op <- options(); on.exit(options(op)) # to reset after each 
+    op <- options(); on.exit(options(op)) # to reset after each
     for (nm in list.files(path, pattern = "[.][RrSsQq]$")) {
        if(trace) cat(nm,":")
        source(file.path(path, nm), ...)
@@ -208,6 +211,16 @@ stopifnot(identical(x, 1:2), identical(y, x^2))
 withAutoprint({ formals(sourceDir); body(sourceDir) },
               max.deparse.length = 20, verbose = TRUE)
 %% --> tests in  ../../../../tests/eval-etc.R
+
+## Continuing after (catchable) errors:
+tc <- textConnection('1:3
+ 2 + "3"
+ cat(" .. in spite of error: happily continuing! ..\n")
+ 6*7')
+r <- source(tc, catch.aborts = TRUE)
+## Error in 2 + "3" ....
+## .. in spite of error: happily continuing! ..
+stopifnot(identical(r, list(value = 42, visible=TRUE)))
 }
 \keyword{file}
 \keyword{programming}

src/library/utils/R/example.R

@@ -23,6 +23,7 @@ function(topic, package = NULL, lib.loc = NULL,
 	 type = c("console", "html"), echo = TRUE, verbose = getOption("verbose"),
          setRNG = FALSE, ask = getOption("example.ask"),
 	 prompt.prefix = abbreviate(topic, 6),
+         catch.aborts = FALSE,
 	 run.dontrun = FALSE, run.donttest = interactive())
 {
     type <- match.arg(type)
@@ -128,5 +129,6 @@ function(topic, package = NULL, lib.loc = NULL,
              prompt.echo = paste0(prompt.prefix, getOption("prompt")),
            continue.echo = paste0(prompt.prefix, getOption("continue")),
            verbose = verbose, max.deparse.length = Inf, encoding = "UTF-8",
+           catch.aborts = catch.aborts,
     	   skip.echo = skips, keep.source=TRUE)
 }

src/library/utils/man/example.Rd

@@ -18,6 +18,7 @@ example(topic, package = NULL, lib.loc = NULL,
         verbose = getOption("verbose"),
         setRNG = FALSE, ask = getOption("example.ask"),
         prompt.prefix = abbreviate(topic, 6),
+        catch.aborts = FALSE,
         run.dontrun = FALSE, run.donttest = interactive())
 }
 \arguments{
@@ -60,6 +61,8 @@ example(topic, package = NULL, lib.loc = NULL,
     device and to any devices opened by the example code.}
   \item{prompt.prefix}{character; prefixes the prompt to be used if
     \code{echo} is true (as it is by default).}
+  \item{catch.aborts}{logical, passed on to \code{\link{source}()},
+    indicating that \dQuote{abort}ing errors should be caught.}
   \item{run.dontrun}{logical indicating that \verb{\dontrun}
     should be ignored.}
   \item{run.donttest}{logical indicating that \verb{\donttest}