Hmmmm... Perl v5.20:

$ perl -MList::Util=first -le 'print first {lc eq "abc"}
    keys %{{ABC=>"ABC"}}'
abc
$ perl -MList::Util=first -le 'print first {uc eq "ABC"}
    keys %{{ABC=>"ABC"}}'
ABC
$ perl -MList::Util=first -le 'print first {/abc/i}
    keys %{{ABC=>"ABC"}}'
ABC
$ perl -MList::Util=first -le 'print first {lc eq "abc"}
    values %{{ABC=>"ABC"}}'
ABC
$ perl -MList::Util=first -le 'print first {lc eq "abc"}
    "ABC"'
ABC
$ perl -MList::Util=first -le 'print first {lc eq "abc"}
    values @{["ABC"]}'
ABC

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On v5.10 they all (except for the last one) give "ABC". The inverse case, first {uc eq "ABC"} keys %{{abc=>"abc"}}, also gives the "unexpected" result "ABC". Smells like a bug... could this be rt://96343?

In reply to Re: Strange behavior with List::Util qw{first} on perl >= 5.20 by Anonymous Monk
in thread Strange behavior with List::Util qw{first} on perl >= 5.20 by papioko

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