From: Ken Bloom <kbloom@...>
Date: 2007-06-12T10:10:08+09:00
Subject: Re: why gsub! doesn't work in my script

On Tue, 12 Jun 2007 02:49:10 +0900, Li Chen wrote:

> 1) what is the best scenario to use Regexp.escape?

You use Regexp.escape when you're building up a regular expression 
programmatically as a String, and using Regexp.new to turn it into a 
regular expression. In that case, all of the control codes in the string 
will be interpreted, so if you have a string that needs to be matched 
literally, then you use Regexp.escape to escape it first. This is also 
the case when using variable interpolation.

airb(main):001:0> a="..."
=> "..."
irb(main):002:0> /#{a}/
=> /.../
irb(main):003:0> /#{Regexp.escape(a)}/
=> /\.\.\./

--Ken

-- 
Ken Bloom. PhD candidate. Linguistic Cognition Laboratory.
Department of Computer Science. Illinois Institute of Technology.
http://www.iit.edu/~kbloom1/