I tried to find an elegant way to avoid map...grep, but only came up with this: 
my %hash2;
map { $hash2{$_} = $hash{$_} if /^NETWORK/ } keys %hash;

[download]
which is fancy-looking, non-map-in-a-void-context way of saying: 
my %hash2;
{ $hash2{$_} = $hash{$_} if /^NETWORK/ } foreach keys %hash;

[download]
My rough check with Benchmark shows no difference between map...grep and map alone until the hash sizes were increased to force memory paging to disk.

[I didn't check to see if anything was optimized away.]

-QM
--
Quantum Mechanics: The dreams stuff is made of

In reply to Re: Re: Hash slices by QM
in thread Hash slices by Marcello

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