This just came up in the CB. Someone wanted to filter an array into two arrays. I decided to be clever and suggested this:

push @{ ($_ % 2) ? @odd : @even }, $_ foreach @numbers;
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That works as expected, but it turned out that the filtering should be done on a regex match. I changed my code to:

push @{ (/PAT/) ? @match : @nonmatch }, $_ foreach @words;
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But that gives a "Bizarre copy of ARRAY in leave" error. Changing it again to:

push @{ (/PAT/) ? \@match : \@nonmatch }, $_ foreach @words;
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gets it working again. And on reflection, that's what should work. So, I guess the original version shouldn't work (you should need to take references in that case as well). But it does. Any explaination?

"The first rule of Perl club is you do not talk about Perl club."
-- Chip Salzenberg