[R] stopifnot with logical(0)

[William Dunlap]

The reason is probably that
   any(logical())
and
   any(!logical())
return FALSE (there are no TRUEs in logical(0)).
Bill Dunlap
TIBCO Software
wdunlap tibco.com


On Fri, Dec 11, 2015 at 5:38 AM, Dario Beraldi <dario.beraldi at gmail.com> wrote:
> Hi All,
>
> I'd like to understand the reason why stopifnot(logical(0) == x) doesn't
> (never?) throw an exception, at least in these cases:
>
> stopifnot(logical(0) == 1)
> stopifnot(logical(0) == TRUE)
> stopifnot(logical(0) == FALSE)
>
> My understanding is that logical(0) is an empty set, so I would expect the
> above tests to fail.
>
> (I got bitten by this in a piece of code where "x" happened to be
> logical(0) and stopifnot didn't catch it)
>
> Thanks!
> Dario
>
>         [[alternative HTML version deleted]]
>
> ______________________________________________
> R-help at r-project.org mailing list -- To UNSUBSCRIBE and more, see
> 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.