package NestedMap;

require Exporter;
@ISA = qw(Exporter);
@EXPORT = qw(nestedmap);

use strict;
use warnings;

# [POD snipped out]

sub nestedmap(&@) {
    my $f = shift;
    map {
        local @NestedMap::stack = ($_, @NestedMap::stack);
        $f->($_);
    } @_
}

##</code><code>##

# show all combinations of (A,B,C) (a,b,c) and (1,2,3)
print join("\n",
  nestedmap {
    nestedmap {
      nestedmap {
        join('',@NestedMap::stack[0..2])
      } qw(A B C)
    } qw(a b c)
  } qw(1 2 3)
);

##</code><code>##

nestedmap { ... } list

##</code><code>##

nestedmap sub { ... }, list