From: nobu.nokada@...
Date: 2004-11-15T09:22:20+09:00
Subject: Re: Dynamic define_method on class creation per module namespace

Hi,

At Mon, 15 Nov 2004 06:37:11 +0900,
trans.  (T. Onoma) wrote in [ruby-talk:120320]:
> I am doing something very similar with a markup parser (made-up example):
> 
>   tr = token_registry {
>     block :literal, '"""', '"""'
>     line :strong, '*', '*'
>     line :italic, '_', '_'
>   }
> 
> One of things that made the methods even better was not having to worry about 
> the namespace for the classes themselves --in other words, the classes Block 
> and Line themselves are, in a way, private.

What about this way?  Though I don't think the name
class_method is proper...


module ClassMethods
  def class_method(name, superclass = ::Object, method = name.to_s.downcase,
                   &definition)
    c = Class.new(superclass, &definition)
    define_method(method, &c.method(:new))
    module_function method
    const_set(name, c)
  end
end

if $0 == __FILE__

  module M
    extend ClassMethods

    class_method(:A) do
      def initialize ; puts "A" ; end
    end

    class_method(:B) do
      def initialize ; puts "B" ; end
    end
  end

  p M.a, M.b
end


-- 
Nobu Nakada