combine two-part regex test

perrin has asked for the wisdom of the Perl Monks concerning the following question:

I have some test code that gets a page with Test::WWW::Mechanize and tries to test its content. The content I'm looking for looks like this:

<tr class="meld">
<th>Security Code Matched</th>
<td>N/A</td>
</tr>
[download]

This is my test code. I had to use two steps to extract the row I want and then check it.

my ($security_code_row) =
    ($mech->content =~ m{Security Code Matched(.*?)</tr>}s);
like($security_code_row, qr{N/A}, 'code matched is N/A');
[download]

Caveats about parsing HTML with regexes aside, can anyone think of a way to do this in one regex (i.e. with $mech->content_like)? It's mostly an academic question, since what I have now is working fine.

Comment on combine two-part regex test Select or Download Code

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Re: combine two-part regex test by Zaxo (Archbishop) on Jan 29, 2007 at 21:07 UTC
HTML parsing aside, I'd prefer two regexen to one containing the two pasted together somehow. The computational complexity of regexen increases dramatically with length. That makes two smaller and simpler ones better in my book. Since what you are looking for seems to be literals, you may want to think of `index` instead of a regex. After Compline, Zaxo	[reply]
Re: combine two-part regex test by AltBlue (Chaplain) on Jan 30, 2007 at 00:24 UTC
fancy experimental features? ;-) `#!/usr/bin/perl -l use strict; use warnings; my @str = split /\n/, <<'HTML'; <tr class="meld"><th>Security Code Matched</th><td>foo</td></tr> <tr><th>Security Code Matched</th><td>N/A</td></tr> <tr><th class="foo">Security Code Matched</th><td>N/A</td></tr> <tr><th>Security Code Matched</th><td>10!</td></tr> <tr><td>Security Code Matched</td><td class="val">N/A</td></tr> HTML for (@str) { if ( m{ \bSecurity\ Code\ Matched\b (.*?)</tr> (?(?{ index($^N, 'N/A') < 0 })!) }xsg ) { print "[[$_]]"; } }` [download] output: `[[<tr><th>Security Code Matched</th><td>N/A</td></tr>]] [[<tr><th class="foo">Security Code Matched</th><td>N/A</td></tr>]] [[<tr><td>Security Code Matched</td><td class="val">N/A</td></tr>]]` [download] i wouldn't use it at home, though ;-) -- AltBlue.	[reply] [d/l] [select]
Re: combine two-part regex test by BrowserUk (Patriarch) on Jan 29, 2007 at 21:11 UTC
Would this work? `m[(?s:<tr.+Security Code Matched.+N/A.+</tr>)]` [download] 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". In the absence of evidence, opinion is indistinguishable from prejudice. "Too many [] have been sedated by an oppressive environment of political correctness and risk aversion."	[reply] [d/l]
Re^2: combine two-part regex test by perrin (Chancellor) on Jan 29, 2007 at 21:26 UTC
The problem is that if a different row in the table contains "N/A", it will still match.	[reply]
Re^3: combine two-part regex test by BrowserUk (Patriarch) on Jan 29, 2007 at 22:57 UTC
And if you tighten the regex to this? `m[(?smx: Security \s+ Code \s+ Matched \s* </th> \s* <td> \s* N/A)];` [download] The only concern I see here is the possibility of the `<td>` having attributes? 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". In the absence of evidence, opinion is indistinguishable from prejudice. "Too many [] have been sedated by an oppressive environment of political correctness and risk aversion."	[reply] [d/l] [select]
Re^4: combine two-part regex test by perrin (Chancellor) on Jan 30, 2007 at 20:12 UTC