You can always use grep if you know what the name will be like: 

use strict;
use warnings;
use Data::Dumper;

my %hash = (
    foo       => 'bar',
    football  => 'Monday',
    one_thing => 'another',
);

my @match = grep /^foo/, keys %hash;
print Dumper \@match;

[download]
But why don't you know the name of the key? That's one of the major reasons to use a hash instead of a regular array (besides using them to find unique keys). Should you be using a regular array instead?

jeffa

L-LL-L--L-LL-L--L-LL-L--
-R--R-RR-R--R-RR-R--R-RR
B--B--B--B--B--B--B--B--
H---H---H---H---H---H---
(the triplet paradiddle with high-hat)

In reply to Re: how to find a key from a hash by jeffa
in thread how to find a key from a hash by jeanluca

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