From: Robert Klemme <shortcutter@...>
Date: 2011-01-20T22:19:42+09:00
Subject: Re: A tad of meta-programming needed

On Mon, Jan 17, 2011 at 9:40 PM, RichardOnRails
<RichardDummyMailbox58407@uscomputergurus.com> wrote:

> Do you have a working example with symbols you could provide me?  And
> what version of Ruby ran it?

Basically you need a mapping from symbols to group indexes to make
named groups work in 1.8.  There are several ways you can do that

1. manual

names = [:foo, :bar, :baz]
...
md = rx.match str
puts md[names.index(:foo) + 1]

2. semi automatic

names = [:foo, :bar, :baz]

def names.get(md, name)
  md[names.index(:foo) + 1]
end
...
md = rx.match str
puts names.get(md, :foo)

3. or even

class MatchData
  attr_accessor :names

  def get(name)
    self[names.index(name) + 1]
  end
end
...
md = rx.match str
md.names = names
puts md.get(:foo)

Further variants are possible.  But I'd switch to 1.9 soon - because
it's faster and has a better regexp engine with named captures.

Kind regards

robert

-- 
remember.guy do |as, often| as.you_can - without end
http://blog.rubybestpractices.com/