Watching a regex match

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

Is there perhaps a CPAN module or some other technique to get a report of how a regex is trying to match as it matches? Maybe something like:

Trying to match atom '\d+'... matched with '83'.
Trying to match atom 'text'... failed at position 20, next character i
+s 'h'.
etc..
[download]

I'm thinking along the lines of what you get from Parse::RecDescent with $RD_TRACE set.

kelan

Perl6 Grammar Student

update (broquaint): s{<(/)?pre>}{<${1}code>}g

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Re: Watching a regex match by Enlil (Parson) on Mar 17, 2003 at 16:15 UTC
You could put `use re 'debug';` at the top of your script. -enlil	[reply] [d/l]
Re: Re: Watching a regex match by kelan (Deacon) on Mar 17, 2003 at 16:19 UTC
Ah, thank you. This is exactly what I was looking for. :) kelan Perl6 Grammar Student	[reply]
Re: Watching a regex match by larsen (Parson) on Mar 17, 2003 at 16:16 UTC
Two links: An article: Rx: A Regex Debugger for Perl A module (that's statically explain regexps, rather than tracing them): YAPE::Regex::Explain	[reply]
Re: Watching a regex match by meetraz (Hermit) on Mar 17, 2003 at 16:53 UTC
One of my favorite tools for doing regex debugging is Komodo's Regex Toolkit (pic here). Basically, you put in your regex & the input data, and then you can step through the matches. It even shows $1,$2,etc... worth checking out.	[reply]
Re^2: Watching a regex match by wazoox (Prior) on Apr 21, 2005 at 11:54 UTC
Here is a link to a fantastic and free tool to test and debug regexps: http://perso.enstimac.fr/~gaborit/lang/perl/regexperiment.pl Kudos to Paul Gaborit!!	[reply]