You can use pairkeys from List::Util, i.e. say for pairkeys f; works fine. You'll need List::Util 1.29 for this function, which is part of the Perl core since 5.20, or you can get it from CPAN.

Update: tybalt89 makes a good point that pairkeys may return duplicate "keys", unlike keys.

In reply to Re: Using 'keys' on a list (updated) by haukex
in thread Using 'keys' on a list by lammey

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