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( #3333=superdoc: print w/replies, xml ) Need Help??

I'm confused with a negative lookahead. Here's some example code. I want it to match on $needs and to not match on $has. The examples 3 and 4 are only as a reference to a fixed string, but I basically want ^($start(.*?))(?!$end)$. Any ideas?

#!/usr/bin/perl use strict; use warnings; my $start = "log4j.rootLogger="; my $startlong = "log4j.rootLogger=INFO, FILE"; my $end = ", SYSLOG"; my $needs = 'log4j.rootLogger=INFO, FILE'; my $has = $needs . ', SYSLOG'; print "needs_matched $needs\n" if $needs =~ /^($start(\w+(,\s)?)+)(?!$ +end)$/; print "has_matched $has\n" if $has =~ /^($start(\w+(,\s)?)+)(?!$end)$/ +; print "needs_matched $needs\n" if $needs =~ /^(log4j.rootLogger=INFO, +FILE)(?!, SYSLOG)$/; print "has_matched $has\n" if $has =~ /^(log4j.rootLogger=INFO, FILE)( +?!, SYSLOG)$/;


In reply to regex: negative lookahead by svenXY

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