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From: jpn@genrad.com (John P. Nelson)
Newsgroups: comp.lang.perl
Subject: Re: does perl have an "in" operator?
Message-ID: <41515@genrad.UUCP>
Date: 15 May 91 18:34:59 GMT
References: <RUSTY.91May14133645@groan.Berkeley.EDU>
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Distribution: comp
Organization: GenRad, Inc., Concord, Mass.
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In article <RUSTY.91May14133645@groan.Berkeley.EDU> rusty@groan.Berkeley.EDU (Rusty Wright) writes:
>I've used a language where with arrays there's an "in" operator that
>checks to see if an element is in an arry.  For example, if you do
>
>	@array = ( 1, 2, 3 );
>
>	if ( 1 in @array ) { print "true\n"; }
>
>it would print true.  Does perl have anything like this?

Well, sort of.  "grep" can be used to implement this fairly easily
using an expression that contains ==:

	if (grep(1 == $_, @array)) { print "true\n"; }

This works essentially the same as your "in" operator.  Unfortunately,
"grep" doesn't stop the first time it finds a match, it iterates over
the whole array no matter what.


     john nelson

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