Hi I want to select only lines beginning with TAG1 *and* ending with TAG2. The first try whith positive look behind and positive look ahead works OK. But the second try with negative look behind doesn't. It prints the lines 1, 2, 3 but aloso the TAGS one. Why ? 
#!/usr/local/bin/perl
#use strict;
use warnings;
#use re debug;

while (<DATA>) {
# This section works OK.
#   if (/(?<=TAG1)(.*)(?=TAG2).*?/x) {
#       print $1, "\n";
#   }

   if (/^(?<!TAGS)(.*?)(?=TAG2).*$/x ) {
       print $1, "\n";
   }
}

__DATA__
TAG1 text one TAG2 etc
TAG1 text two TAG2 etc
TAG1 text three  TAG2 etc
TAGS text four TAG2 etc
TAG1 text five TAGT etc

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-- cmic. Life helps. Perl Too.

In reply to negative look behind (again) by cmic

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