| \name{chkDots} |
| \alias{chkDots} |
| \title{Warn About Extraneous Arguments in the "..." of Its Caller} |
| \description{ |
| Warn about extraneous arguments in the \code{...} of its caller. A |
| utility to be used e.g., in S3 methods which need a formal \code{...} |
| argument but do not make any use of it. This helps catching user |
| errors in calling the function in question (which is the caller of |
| \code{chkDots()}). |
| } |
| \usage{ |
| chkDots(..., which.call = -1, allowed = character(0)) |
| } |
| \arguments{ |
| \item{...}{\dQuote{the dots}, as passed from the caller.} |
| \item{which.call}{passed to \code{\link{sys.call}()}. A caller may |
| use -2 if the message should mention \emph{its} caller.} |
| \item{allowed}{not yet implemented: character vector of \emph{named} |
| elements in \code{...} which are \dQuote{allowed} and hence not |
| warned about.} |
| } |
| \author{Martin Maechler, first version outside base, June 2012.} |
| \seealso{ |
| \code{\link{warning}}, \code{\link{...}}. |
| } |
| \examples{ |
| seq.default ## <- you will see ' chkDots(...) ' |
| |
| seq(1,5, foo = "bar") # gives warning via chkDots() |
| |
| ## warning with more than one ...-entry: |
| density.f <- function(x, ...) NextMethod("density") |
| x <- density(structure(rnorm(10), class="f"), bar=TRUE, baz=TRUE) |
| } |
| \keyword{utilities} |