This is trivial using List::Pairwise, even if the values aren't unique. 

use List::Pairwise 'mapp';

my %hash = (
    foo => 1,
    bar => 2,
    baz => 1,
    bux => 0,
);
my $val = $hash{foo};

my @keys = mapp { $b eq $val ? $a : () } %hash;

print "@keys";

__END__
baz foo

[download]
Even if you think that your values are unique it's sometimes a good idea to assert this: 
my ($key, @too_many) = mapp { $b eq $val ? $a : () } %hash;
! @too_many
    or die 'Too many ...';

[download]

lodin

In reply to Re: getting hash key with value (List::Pairwise) by lodin
in thread getting hash key with value by sovixi

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