# ! perl -slw
use strict;

sub nForS(&$@) {
    my $code = shift;    die "First argument must be a code ref"   unless ref( $code ) eq 'CODE';
    my $aref = shift;    die "second argument must be an array ref" unless ref( $aref ) eq 'ARRAY';

    my @limits = @_;

    our @indices; local *indices = $aref;

    @indices = ( 0 ) x @limits unless @indices;

    for( my $i = $#limits; $i >= 0; ) {
        $i = $#limits;
        $code->( @indices ), ++$indices[ $i ]
            while $indices[ $i ] < $limits[ $i ];
        $i = $#limits;
        $indices[ $i ] = 0, ++$indices[ --$i ]
            while $i >= 0 and $indices[ $i ] == $limits[ $i ];
    }
}

my @state;
my $n = 10;
nForS{ print "@_\n"; last unless --$n } \@state, 3, 6, 9;

print "First 10 permutations; enter to see the rest"; <STDIN>;

nForS{ print "@_\n"; } \@state, 3, 6, 9;