Thank you, but unfortunately no.
The "def" will only be a part of the line. If "def" occurs anywhere in the line I want it included.

#!/usr/bin/perl

# full script the following one liner:
# $ echo -e "abc\ndef\nghi\n" | perl -wlne '! /def/ and print "$_";'
# abc
# ghi

use strict;
use warnings;
use diagnostics;

my $B = "";
my $A = "abcdef
fhijkl
mnopqr
";

while ( $A =~ m{(.+)}g ) {
   $B .= "$1\n" unless $1 =~ /ijk/;
}
print "\$B = \n$B\n";


$B = "";
while ( $A =~ m{(.+)}g ) {
   $B .= "$1\n" while $1 =~ /ijk/;
}
print "\$B = \n$B\n";

[download]

$B =
abcdef
mnopqr
Use of uninitialized value $1 in concatenation (.) or string at ./ExtractTest.pl line 26 (#1)

Isn't "while" suppose to be the opposite of "unless"?

In reply to Re^2: Regex match on implicit default variable ($_) in a script, not a one liner by Todd Chester
in thread Regex match on implicit default variable ($_) in a script, not a one liner by Todd Chester

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