> I agree that it is non-trivial to solve the cases you & I have posed. > However, I would wholeheartedly support having an error spit back for any > function that does not explicitly support a class. In this case, if I > attempt to do sapply(x, class), and 'x' is of class "difftime", then I > should receive an error "sapply cannot function upon class 'difftime' ". > Why do I take this stance? There are at least 2 strong reasons:
I don't see why that command should be a problem because class() returns a string. A better example might be sapply(x, identity) which in general you would hope to be identical to x: x <- structure(1:10, class = "blah") identical(x, sapply(x, identity)) # [1] FALSE Hadley -- Assistant Professor / Dobelman Family Junior Chair Department of Statistics / Rice University http://had.co.nz/ ______________________________________________ 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.
