On Sunday, 19 December 2021, 13:28:23 CET, Oodler 577 <oodler577@sdf-eu.org> wrote: > Thank you, this is super helpful. My final comment is just to > reiterate what I most recently said; as long as this doesn't > affect how things currently work with undef/q{}/0 and existing > built-ins/ops; and we get a C<unknown> built-in that does for > unknown values what C<defined> does for undef'd values, For interpolation, I would suggest it behave like undef, but with a warning. I would (only half-joking here), also consider it to stringify to U+FFFD REPLACEMENT CHARACTER. my $name = unknown; say "Hello, $name!"; Output: Use of unknown value $name in say at ... Hello, �! > As an exercise, I wonder how many use cases for undef would remain > if unknown was available. If the answer is "not many", then maybe > the answer would be a compatible tweak to undef and not the > creation of a new special value. Just a thought... I would not recommend changing current behavior of undef. That would be widespread carnage. Best, Ovid -- IT consulting, training, specializing in Perl, databases, and agile development http://www.allaroundtheworld.fr/. Buy my book! - http://bit.ly/beginning_perlThread Previous | Thread Next