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Greetings jesuashok,

It's a very curious line, and others have explained what it does already; however, it has a couple negatives: It's not easily understood, and it's slower than a more easily understood alternative.

use strict; use warnings; use Benchmark qw(cmpthese); cmpthese( 100000, { 'ahash' => sub { my $pat = {qw(a - b = c ~ d ^)}->{substr($0, 0, 1)}; }, 'tr' => sub { (my $pat = substr($0, 0, 1)) =~ tr/abcd/-=~^/; }, }, );

The above benchmark returns this:

Rate ahash tr ahash 75120/s -- -86% tr 541712/s 621% --

It's a nice trick, but I wouldn't use it anywhere except in an obfu.

gryphon
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In reply to Re: Interesting line which I read from Monk's snippets by gryphon
in thread Interesting line which I read from Monk's snippets by jesuashok

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