foo<- function(x,help=FALSE,...) { helpout<-c(comment, comment, end of comments) if(something_is_wrong_with_inputs || help=TRUE) { print(helpout) stop #or trycatch, or whatever you prefer } [remainder of function] } I know that's sloppy but I'm new to R. Carl ______________________________________________ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.
Along the lines of Gabor's method, presumably you could put a "spare"
argument in your function: