hash_map

gistfile1.pl

#!/usr/bin/perl 

use 5.10.0;

use strict;
use warnings;

sub hash_map(&+) {
    my( $sub, $hash ) = @_;
    my @mapped;

    push @mapped, $sub->() 
        while ($a,$b) = each %$hash;

    return @mapped;
}

my %my_hash = (
    a => 1,
    b => 2,
    c => 3,
);

say for hash_map { "$a : $b" } %my_hash;

say for hash_map { "$a : $b" } { z => 3 };