Re^2: Regex match on implicit default variable ($

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"?

Comment on Re^2: Regex match on implicit default variable ($_) in a script, not a one liner Download Code

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Re^3: Regex match on implicit default variable ($_) in a script, not a one liner by hippo (Archbishop) on Oct 24, 2015 at 09:08 UTC
Isn't "while" suppose to be the opposite of "unless"? No it isn't. "while" is the opposite of "until". The opposite of "unless" is "if". All of this is in the fine documentation of Compound Statements.	[reply]
Re^3: Regex match on implicit default variable ($_) in a script, not a one liner by BrowserUk (Patriarch) on Oct 24, 2015 at 06:31 UTC
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` [download] With the rise and rise of 'Social' network sites: 'Computers are making people easier to use everyday' Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error. "Science is about questioning the status quo. Questioning authority". I knew I was on the right track :) In the absence of evidence, opinion is indistinguishable from prejudice.	[reply] [d/l]