use strict;
use warnings;
use Data::Dump qw/pp dd/;
use Test::More;

sub matrix3 (&@){
    my ($code,@dims) = @_;

    my @coor =(undef)x@dims;

    my $rec;
    $rec = sub  {
        my @dims =@_;

        return $code->(@coor) unless @dims;

        my $level  = - @dims;
        my $max    = shift @dims;
        my $cursor = \$coor[$level];

        my @arr;

        for ( 0 .. $max ) {
            $$cursor = $_;
            $arr[$_] = $rec->(@dims);
        }

        return \@arr;
    };

    return $rec->(@dims);
}



my $a_matrix = matrix3 {"<@_>"} 3,2,1;





my @classic;
for my $x (0..3) {
    for my $y (0..2) {
        for my $z (0..1) {
            $classic[$x][$y][$z] = "<$x $y $z>";
        }
    }
}




is_deeply($a_matrix,\@classic,"same matrix");

pp \@classic;

done_testing;