gistfile1.pl

#!/usr/bin/env perl
use strict;
use warnings;
use Perl6::Say;
use Data::Dumper;
#use Test::More qw(no_plan);

sub p ($) {
    say Dumper @_;
}

sub radix_sort {
    my ($array, $keys) = @_;
    for my $key (@$keys) {
        my @bucket;
        push @{ $bucket[$key->($_)] ||= [] }, $_ for @$array;
        $array = [ map {@{$bucket[$_]}} grep {$bucket[$_]} (0..9) ];
    }
    return $array;
}

p radix_sort([ 1, 14, 3, 25, 101, 5, 321, 9], [
    sub { $_[0]       % 10 }, #  1 2|3|
    sub { $_[0] / 10  % 10 }, #  1|2|3
    sub { $_[0] / 100 % 10 }, # |1|2 3
]);