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Re: problem using regexp

by Grimy (Pilgrim)
on Jul 27, 2012 at 20:36 UTC ( #984094=note: print w/replies, xml ) Need Help??

in reply to problem using regexp

The problem here is overlapping matches. The space between the first and the second occurence of /a/i is part of both possible matches. Since it is gobbled by the first match, the second /a/i doesn't match.

It is possible to "rewind" your regex by assigning to pos. See 'pos' in perldoc.

#! usr/bin/perl use strict; use warnings; $_=' A a A '; while (/(\s)(a)(\s)/ig) { print "The text matches the pattern '$&' at position " . pos() . " +.\n"; # uncomment this to rewind #pos() = pos() - 1; }

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Re^2: problem using regexp
by artifact (Novice) on Jul 29, 2012 at 16:05 UTC
    it works!! it also made me learn few other concepts.

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