From: Stefano Crocco <stefano.crocco@...>
Date: 2008-03-03T19:17:58+09:00
Subject: Re: Patterns for error messages

Alle Monday 03 March 2008, Victor 'Zverok' Shepelev ha scritto:
> >This should take care of all the four patterns:
> >
> >/^(?:.*:\d+:in\s+`require':\s+|\s+\^\s+from\s+)?(.*)(?=:\d+)/
>
> But not this one:
>
> "./../app/models/teachers.rb:7:in `initialize': undefined local variable"

I think this is a different matter: here, we're in the first case (the
simplest) and the regexp correctly gives:

"./../app/models/teachers.rb"

This is the path of the file where the error occurs, relative to the directory 
where ruby was started. What would you like to get here?

> (not saying about that most of regexp engines too dumb for doing ?: and ?=
> groups).

Are they? I didn't try many editors (in particular, kate and vim on linux),
but they all support them. At any rate, I think you can do without them. If
you replace the initial (?: with a simple (, you'll get the name of the file
in the second group instead of the first. The look-ahead at the end can be
removed by replacing (.*) with [^:]*. which matche any character except the 
column. This has the side effect of not working with filenames containing ':' 
(this is the reason I used the look-ahead).

Stefano