From: nobu.nokada@...
Date: 2003-06-01T01:35:15+09:00
Subject: Re: regexp operators

Hi,

At Sun, 1 Jun 2003 00:10:15 +0900,
Wesley J Landaker wrote:
> Well, + meaning concatination makes sense to me. What else would it 
> mean? Notice that I do put regexps in (?:) groups so that you don't 
> have any ambiguity if you do something like:
> 
> /foo|bar/ + /.*/   # => /(?:foo|bar)(?:.*)/u  

One possibility:
=> /(?:foo|bar).*(?:.*)/u

> One thing that's missing from the packages you point at is that the 
> object you get back isn't completely usable as a regexp. They could be 
> extended to have the missing methods, of course, but they don't 
> currently support them. And if you've added or modified any methods in 
> regexp, these objects are of a different type (and aren't class 
> descendants) so won't have the changes applied to them (say, if I 
> redefine to_s or source or something like that)

Yes, I know it's a problem.  Not only you mentioned, some
methods of String expect Regexp instance.

> BTW, I never wrote '&' because I didn't really need it, but it could be 
> done with something like this:
> 
> In RegexpOps.rb:
> # the other code I posted goes here
> class Regexp
>   def &(other)
>     /(?=#{self})#{other}/u
>   end
> end

Seems nice.

> Of course, that regexp will never match anything, but you get the idea. 
> ;)

Maybe, /(?=.*(?:foo)).*(?:bar)/?

-- 
Nobu Nakada