chkDots {base}R Documentation

Warn About Extraneous Arguments in the "..." of Its Caller


Warn about extraneous arguments in the ... of its caller. A utility to be used e.g., in S3 methods which need a formal ... 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 chkDots()).


chkDots(..., = -1, allowed = character(0))



“the dots”, as passed from the caller.

passed to A caller may use -2 if the message should mention its caller.


not yet implemented: character vector of named elements in ... which are “allowed” and hence not warned about.


Martin Maechler, first version outside base, June 2012.

See Also

warning, ....


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)

[Package base version 3.5.0 Index]