#!/usr/bin/perl
use strict;
use warnings;
use Algorithm::Loops qw( NestedLoops );

my @products = qw(tshirt pants  sweatshirt socks shoes);
my %options = (
    sizes  => [ qw(small  medium large extra-large) ],
    colors => [ qw(red green blue) ],
    brands => [ qw(foo bar blah asdf) ]
);

my @Loops;
push @Loops , \@products;
push @Loops , $options{$_} for keys %options; 
my $iter = NestedLoops( \@Loops );

my @combo;
print "@combo\n" while ( @combo = $iter->() );