base (version 3.0.3)

warnings: Print Warning Messages

Description

warnings and its print method print the variable last.warning in a pleasing form.

Usage

warnings(...)

Arguments

...

arguments to be passed to cat.

Warning

It is undocumented where last.warning is stored nor that it is visible, and this is subject to change. Prior to R 2.4.0 it was stored in the workspace, but no longer.

Details

See the description of options("warn") for the circumstances under which there is a last.warning object and warnings() is used. In essence this is if options(warn = 0) and warning has been called at least once.

It is possible that last.warning refers to the last recorded warning and not to the last warning, for example if options(warn) has been changed or if a catastrophic error occurred.

References

Becker, R. A., Chambers, J. M. and Wilks, A. R. (1988) The New S Language. Wadsworth & Brooks/Cole.

See Also

warning.

Examples

## NB this example is intended to be pasted in,
##    rather than run by example()
ow <- options("warn")
for(w in -1:1) {
   options(warn = w); cat("\n warn =", w, "\n")
   for(i in 1:3) { cat(i,"..\n"); m <- matrix(1:7, 3,4) }
}
warnings()
options(ow) # reset
tail(warnings(), 2) # see the last two warnings only (via '[' method)