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Postings from January 2022
On Wednesday, 19 January 2022, 19:00:12 CET, Paul "LeoNerd" Evans <leonerd@leonerd.org.uk> wrote:
> sub signatured($x = undef) {
> # impossible to distinguish signatured() from signatured(undef)
> }
I knew my 3VL discussion went over like a lead balloon, but I couldn't resist being cheeky ...
use Unknown::Values;
sub foo ($bar = unknown) {
say is_unknown $bar ? "unknown" : "known";
}
foo();
That prints "unknown", so if someone passed in `undef`, it will print "known" because someone explicitly assigned to it.
Best,
Ovid
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