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Re: /(\w|(?{++$n}))*/

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From:
Jeff 'japhy' Pinyan
Date:
October 29, 2003 13:25
Subject:
Re: /(\w|(?{++$n}))*/
Message ID:
Pine.LNX.4.44.0310291624490.2666-100000@perlmonk.org
On Oct 29, Mark Jason Dominus said:

>> On Oct 29, Jeff 'japhy' Pinyan said:
>>
>> And somewhat related, why doesn't
>>
>>   "abc" =~ /(b?|[ac])*/;
>>
>> match 'abc'?  It matches '' (the zero b's at the beginning of the string).
>
>Why should it match 'abc'?  The first alternative alternative b? is
>taken before the seoncd alternative [ac]* .
>
>The * operator has special code in it to prevent it from going into an
>infinite loop when its argument has matched an empty string, so the *
>loop is exited after the first pass.

Hrm.  I guess I was confusing that with /\w??/g.

-- 
Jeff "japhy" Pinyan      japhy@pobox.com      http://www.pobox.com/~japhy/
RPI Acacia brother #734   http://www.perlmonks.org/   http://www.cpan.org/
<stu> what does y/// stand for?  <tenderpuss> why, yansliterate of course.
[  I'm looking for programming work.  If you like my work, let me know.  ]


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