Without digging into the perl code I can't be sure (although it's likely someone will know for sure), but that isn't really how a hash works. In any implementation I'm aware of there is no explicit list of key values and any equivalent of an in place edit of the keys would require about as much work under the hood as your slice/delete approach. See Hash_table to get an idea of what is going on under the hood.

Optimising for fewest key strokes only makes sense transmitting to Pluto or beyond

In reply to Re: can I change hash keys or values directly by GrandFather
in thread can I change hash keys or values directly by misterperl

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