use strict;
use warnings;
use Set::CrossProduct;

my @products = ('tshirt', 'pants',  'sweatshirt');

my %options = (
    'sizes'  => ['small', 'medium', 'large'],
    'colors' => ['red',   'green',  'blue']
);

# build an array of array
my @p = ();
push @p, \@products;
push @p, $options{$_} for sort keys %options;

# get all combinations
my $iterator = Set::CrossProduct->new( \@p );

# print the combinations
local $, = ' ';
print "@$_\n" for (@{$iterator->combinations});
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