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Re: regex: negative lookahead

by Khen1950fx (Canon)
on Dec 05, 2011 at 20:50 UTC ( #941919=note: print w/replies, xml ) Need Help??


in reply to regex: negative lookahead

I've never had a the need to use a lookaround, but your question piqued my curiosity. As an experiment, I used Regexp::Assemble to rework your example because it just does the right thing with assertions, lookaheads, and lookbehinds.
#! /usr/bin/perl -slw use strict; use Regexp::Assemble; my $needs = Regexp::Assemble->new->add( qw[ FILE INFO ] ); my $has = Regexp::Assemble->new->add( qw[ FILE INFO SYSLOG ] ); while( defined( $_ = <DATA> )) { chomp; if( /($needs)/ ) { print $needs->as_string; } } while( defined( $_ = <DATA> )) { chomp; if( /($has)/ ) { print $has->as_string } } __DATA__ FILE INFO SYSLOG
I believe, if I"ve understood you correctly, that it works the way that it should. What do you think?

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[GotToBTru]: un less you're working on write-only memory
[1nickt]: my $x = $aohoaoh->[0]->{' foo'}->[0]->{'bar' }; should work
[thepkd]: not indexing
[thepkd]: getting data out of the ds
[choroba]: it depends. Give more details, please
[thepkd]: i used a series of {}'s but it dont work
[choroba]: You need square brackets for arrays
[GotToBTru]: you can certainly construct a single expression to access any part of the data structure, without using temp variables. but you might make it easier on yourself and any other poor soul who has to understand your code if you do
[thepkd]: to dereference i mean
LanX .oO( oh tempz, oh moretz)

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