Nope. It is caused by factoring yet another lookup out of the inner loop.

In languages like C this kind of optimization is meaningless because the compiler is smart enough to know when to do it for you. But Perl has to make a trade-off between compiling well and runtime performance, so doesn't make this trade-off.

If Perl had a JIT compiler then this would go away as well. The Parrot folks have promised a JIT compiler for Perl 6, but I've stopped holding my breath on waiting for that to happen.

In reply to Re^10: How to speed up a nested loop? by tilly
in thread How to speed up a nested loop? by Xenofur

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