Re: regex exercise

#!/usr/bin/perl

use strict;
use warnings;

$_ = join '', <DATA>;

s/(<p>(?:(?!<\/p>).)*<\/p>)(??{-1 == index $1, "\n\n" and '(*FAIL)'})/
+-->$1<--/gs;

print;

__DATA__
a 123 456 789
b 123 456 789

c 123 456 789
d 123 456 789

<p>e 123 456 789
f 123 456 789</p>

<p>e 123 456 789
f 123 456 789
g 123 456 789
h 123 456 789</p>

<p>1 123 456 789
2 123 456 789

3 123 456 789
4 123 456 789</p>
[download]

Comment on Re: regex exercise Download Code

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Re^2: regex exercise by Anonymous Monk on Aug 02, 2016 at 23:26 UTC
Even this (they finally fixed the nested regex problem) `s/(<p>(?:(?!<\/p>).)<\/p>)(??{$1 !~ m#\n\n# and '(FAIL)'})/-->$1<--/ +gs;` [download]	[reply] [d/l]