The "def" will only be a part of the line. If "def" occurs anywhere in the line I want it included.

This perhaps?:

#!/usr/bin/perl

use strict;
use warnings;
use diagnostics;

my $A = "abcdef
fhijkl
mnopqr
redefine
";

( my $B = $A ) =~ s[(^.+\n)][ my $x = $1; $x !~ /def/ ? '' : $x ]gme;

print "$B";

__END__
C:\test>1145825.pl
abcdef
redefine

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In reply to Re^3: Regex match on implicit default variable ($_) in a script, not a one liner by BrowserUk
in thread Regex match on implicit default variable ($_) in a script, not a one liner by Todd Chester

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