The recursion can be simplified, since $level depends on the length of the remaining dimensions in @_.
I also used a "fancy" trick with $cursor as ref to the @coor array.
(EDIT: Of course there is still more room for improvement, it depends if clarity or speed matters)
use strict;
use warnings;
use Data::Dump qw/pp dd/;
use Test::More;
sub matrix2 (&@){
my $code = shift;
my @coor;
my $depth = @_;
my $rec;
$rec = sub {
return $code->(@coor) unless @_;
my $level = $depth - @_;
my $max = shift;
my $cursor = \$coor[$level];
my $arr = [
map {
$$cursor = $_;
$rec->(@_)
} 0 .. $max
];
return $arr;
};
$rec->(@_);
}
my $a_matrix = matrix2 {"<@_>"} 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;
ok 1 - same matrix
[
[
["<0 0 0>", "<0 0 1>"],
["<0 1 0>", "<0 1 1>"],
["<0 2 0>", "<0 2 1>"],
],
[
["<1 0 0>", "<1 0 1>"],
["<1 1 0>", "<1 1 1>"],
["<1 2 0>", "<1 2 1>"],
],
[
["<2 0 0>", "<2 0 1>"],
["<2 1 0>", "<2 1 1>"],
["<2 2 0>", "<2 2 1>"],
],
[
["<3 0 0>", "<3 0 1>"],
["<3 1 0>", "<3 1 1>"],
["<3 2 0>", "<3 2 1>"],
],
]
1..1