Yes, 30 hash lookups is slower than walking an array with foreach.

OTOH one hash lookup is much faster than walking a good chunk of an array.

If you can arrange that straight lookups happen more often than having to walk the whole cache, then you should get a performance win. (See code in my other node.)

In reply to Re (tilly) 4: Efficiency Question by tilly
in thread Efficiency Question by mr.nick

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