Re: regex match after pattern

Don't use regular expressions to parse HTML. Use a proper parser:

#!/usr/bin/perl
use warnings;
use strict;

use XML::LibXML;

my $html = 'XML::LibXML'->load_html( string => << '__HTML__');
<form method="post" action="logout.lp" name="authform" id="logoutform"
+>
        <input type="hidden" name="rn" value="-1383135969">
<form method="post" action="login.lp" name="authform" id="authform">
        <input type="hidden" name="rn" value="-1383135969">
__HTML__

my $value = $html->findvalue('//form[@action="login.lp"]/input[@name="
+rn"]/@value');
print $value, "\n";
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Comment on Re: regex match after pattern Download Code

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Re^2: regex match after pattern by marinersk (Priest) on Mar 12, 2015 at 16:05 UTC
I've got just shy of four million reasons why a proper parser should be used for this purpose. But the inquisitive engineer in me wants to know: Under what conditions (not including fear of modules) might one justify not using the proper parser procedure?	[reply]
Re^3: regex match after pattern by choroba (Cardinal) on Mar 12, 2015 at 16:08 UTC
I'd use the regex approach if the input in question was generated from a known template that would never change, which means all the whitespace would always be in the sampe place. Or in a one-time script I'll never run again. Which makes it almost never. :-) لսႽ† ᥲᥒ⚪⟊Ⴙᘓᖇ Ꮅᘓᖇ⎱ Ⴙᥲ𝇋ƙᘓᖇ	[reply]
Re^3: regex match after pattern by Anonymous Monk on Mar 12, 2015 at 22:59 UTC
Under what conditions (not including fear of modules) might one justify not using the proper parser procedure? When you know how to write and debug the regular expression yourself ;) and understand the risks	[reply]
Re^2: regex match after pattern by littleperl (Initiate) on Mar 13, 2015 at 14:58 UTC
thank you for the quick response. Indeed why did I not opt for a parser, not sure, didn't use my head will probably is the most apropriate answer :) stepping away from the regex idea for this pattern search then.	[reply]