From: "Hal E. Fulton" <hal9000@...>
Date: 2002-08-01T01:06:57+09:00
Subject: Re: Individual elements of regular expressions

----- Original Message -----
From: "Maur�cio" <briqueabraque@yahoo.com>
Newsgroups: gmane.comp.lang.ruby.general
To: "ruby-talk ML" <ruby-talk@ruby-lang.org>
Sent: Wednesday, July 31, 2002 9:10 AM
Subject: Individual elements of regular expressions


>     How do I say: in a set of (number G number number1 number number
> end-of-line --CONT- number number2 number number end-of-line), I want to
> know number1 and number2?

I think David perhaps answered half your question...
I'll address the other half.

I think you want backreferences. If you parenthesize
part of a regex, then you can retrieve it afterward
as a separate entity. You can use the Perlish
shorthand \1, \2, etc. in some cases or you can use
the array-like MatchData object.

Look it up in the Pickaxe Book or in _The Ruby Way_.

A MatchData example (doing this from memory, so it
may be wrong):

  reg = /(.)2(.)2/
  str = "R2D2"
  md = reg.match(str)
  puts md[0]  # "R2D2" (the entire match)
  puts md[1]  # "R"
  puts md[2]  # "D"

Hope this helps.

Hal