Thanks, your code is indeed terser but I wouldn't really call it more elegant ;)

I'll need to benchmark it to see if my (elegant?) referencing and shifting of the range result in a penalty. Readability (in the eye of the beholder) is my second goal.

I don't want to loop over iterators (yet), that's again another (third) semantic.

I need only nested loops, to make the interface intuitive for the users

for my $x ( $sub_x->() ) {
    for my $y ( $sub_y->() ) {
         return [ $x,$y ];
    }
}

[download]

From what I understand are you caching the values for the next iteration, this brakes my semantics and might cause side effects.

Cheers Rolf
(addicted to the Perl Programming Language :)
Wikisyntax for the Monastery

In reply to Re^4: Efficient but elegant Cross-Product iterator ? (updated) by LanX
in thread Efficient but elegant Cross-Product iterator ? by LanX

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