Re: Things in lists'n'stuff.

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Post #201,308 by dws 3/30/05 3:34:32 PM Reply	Re: Things in lists'n'stuff. That snippet (with "map" changed to "grep") will match substrings, giving you false positives (unless that's what you want). Try `if (grep {$_ eq $thing} @array) { do stuff; }` if you're probing once. If you're going to probe multiple times, turn @array into a hash, and do `if ($hashed_array{$thing}) { do stuff; }`
Post #201,318 by Simon_Jester 3/30/05 4:39:03 PM 3/30/05 4:39:38 PM Reply	Even if only once.... if you're looking in an array (for an exact match), you probably want the hash. Edited by Simon_Jester March 30, 2005, 04:39:38 PM EST Expand All History
Post #201,320 by ben_tilly 3/30/05 5:22:51 PM Reply	Only if you're going to repeat the operation a few times Building a hash is slower than scanning the array. Accessing a hash many times is faster than scanning the array many times. At some fairly small fixed number, building the hash is worthwhile. That number varies with OS, version of Perl, and what parameters Perl was built with. I tested it once at 7, but that is probably not true any more. Cheers, Ben I have come to believe that idealism without discipline is a quick road to disaster, while discipline without idealism is pointless. -- Aaron Ward (my brother)

Things in lists'n'stuff. - (pwhysall) - (3) - March 30, 2005, 01:52:20 PM EST

Re: Things in lists'n'stuff. - (dws) - (2) - March 30, 2005, 03:34:32 PM EST

Even if only once.... - (Simon_Jester) - (1) - March 30, 2005, 04:39:38 PM EST

Only if you're going to repeat the operation a few times - (ben_tilly) - March 30, 2005, 05:22:51 PM EST

... and then the Earth cooled.
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