From: Robert Klemme <bob.news@...>
Date: 2004-05-17T16:24:00+09:00
Subject: Re: Namespaces (was [RCR] subclasses of string as hash keys)


"Matthias Georgi" <matti_g@gmx.de> schrieb im Newsbeitrag
news:opr71j8uur7zr67k@mail.gmx.net...

<snip>example code</snip>

> Every missing method for a normal String object will be intercepted,
> and the object gets extended with a module in the calling environment.
> That's actually what we needs.
> My own extensions are only used in my modules.
> The code above is only a demonstration of the algorithm.
> There is a problem left, I cannot pass the strings outside
> my module, because other people are expecting the standard
> String interface, so the whole thing should be integrated in the
> language core without singleton classes, extending only for the
> actual method call.

If that functionality is only needed inside the module then IMHO there is
a much easier way to accomplish this: define functions in a namespace aka
define module methods:

module Foo
  def reformat(str)
    str.gsub!(/^(.*)$/, '[\\1]')
    str
  end

  class Test
    include Foo

    def initialize(s);@s=s;end

    def do_something
      puts reformat( @s ).length
    end
  end
end


module Bar
  def reformat(str)
    str.gsub!(/^(.*)$/, '<<\\1>>')
    str
  end

  class Test
    include Bar

    def initialize(s);@s=s;end

    def do_something
      puts reformat( @s ).length
    end
  end
end

>> t1 = Foo::Test.new("xx")
=> #<Foo::Test:0x10177218 @s="xx">
>> t1.do_something
4
=> nil
>> t2 = Bar::Test.new("xx")
=> #<Bar::Test:0x1016f700 @s="xx">
>> t2.do_something
6
=> nil

Regards

    robert