How about:

sub genIterator {
    my ($len,$count) = @_;
    my @list = ();
    return sub {
        if (@list == 0 || @list < $len) {
            push @list, 0;
        } else {
            $list[-1]++;
            while (@list && $list[-1] >= $count) {
                pop @list;
                $list[-1]++ if @list;
            }
        } 
        return @list ? join("", @list) : undef;
    }

}

[download]

Note that the code to iterate should be:

my $iter = genIterator(4,3);
print while defined($_ = $iter->());

[download]

since 0 evaluates as false.

In reply to Re: In need of a sequence iterator. by !1
in thread In need of a sequence iterator. by BrowserUk

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