Every now and then I need to create a n-dimensional array from some given formula, where n almost always is 1 or 2.
I've been searching for a module providing such functionality without success. It would be a surprise if there really wasn't such a thing.

But so I rolled my own and came to this:

# arg_1 to arg_n specify size in dimension k,
# last arg is a reference to a sub
# - expecting n arguments x1 ... xn
# - returning the desired value at $na->[x1]...[xn]
sub narray {
    my $size = shift;
    my $val = pop;
    my $na;
    for my $i (0 .. $size - 1) {
        $na->[$i] = @_ ? narray(@_, sub {&$val($i, @_)}) : &$val($i);
    }
    $na;
}
[download]

which can be used in various ways and is not limited in dimension:

$ar = narray(3, sub {$_[0]});
# [0, 1, 2]

$mr = narray(3, 3, sub {$_[0] == $_[1] || 0});
# [[1, 0, 0], [0, 1, 0], [0, 0, 1]]
[download]

just to get an idea.

Does anybody know of a module providing something similar?
Otherwise: Is this of use for someone else or would it even fit into something existing?

UPDATE 1: This would be more perlish if the sub ref argument came first and the sub itself was prototyped:

sub narray (&@);

$ar = narray {$_[0]} 3;
[download]

UPDATE 2: Incorporating LanX's suggestion of using map into UPDATE 1 results in:

sub narray (&@);
sub narray (&@) {
    my $val = shift;
    my $size = shift;

    [map {my $i = $_; @_ ? narray {&$val($i, @_)} @_ : &$val($i)} (0 .
+. $size - 1)];
}

my $na = narray {"<@_>"} 3, 2
# [['<0 0>', '<0 1>'], ['<1 0>', '<1 1>'], ['<2 0>', '<2 1>']]
[download]

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