From: Yukihiro Matsumoto <matz@...>
Date: 2004-11-12T01:52:00+09:00
Subject: Re: #scan with or'd (`|`) subexpressions.

Hi,

In message "Re: #scan with or'd (`|`) subexpressions."
    on Thu, 11 Nov 2004 23:29:58 +0900, "trans.  (T. Onoma)" <transami@runbox.com> writes:

|Does the new Ruby regexp engine do this?
|
|  irb(main):001:0> '1234'.scan(/(1)(2)|(3)(4)/)
|  => [["1", "2", nil, nil], [nil, nil, "3", "4"]]
|  irb(main):002:0>
|
|Why would all the subexpressions be listed when there is an `|` (or) used? I 
|expected:
|
|  => [["1", "2"], ["3", "4"]]

You will never know which subexpression is matched, if you get your
expected result.  Is there any reason /(1|3)(2|4)/ is not sufficient?

							matz.