It would depend on what you are trying to do, probably. The one thing I've noticed is that usually I don't actually need a new hash: I just need to know which values are in the new hash.

My other trick would be to split it into two lines, and use a hash slice:

@new_keys = grep { $hash{$_} == $condition } keys %hash;
@new_hash{@new_keys} = @hash{@new_keys};

[download]

I'm sure there are other ways, but that's fairly short and clear.

(Fixed: Thanks lostjimmy.)

In reply to Re^2: map and grep (but for hashes) by DStaal
in thread map and grep (but for hashes) by zerohero

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