From: Stephen White <spwhite@...>
Date: 2001-08-23T13:26:31+09:00
Subject: [ruby-talk:20158] Re: Another Possible RCR - Wrappers via Mixins

On 23 Aug 2001 12:27:21 +0900, Dave Thomas wrote:
> Except... let's not call it 'super' as that's kind of misleading. How
> about 'inner', or 'chain'?

I'm visualising this as:

There is a class, which has variables and methods. Calls to this class
"fall through" to the parent class. If the class has defined the method
as well, this method can wrap the parent method, eg:

  class Test1
    def test str
      puts str
    end
  end

  class Test2 < Test1
    def test str
      puts "1"
      super
      puts "2"
    end
  end

  Test2.new.test "hello world"

should (I didn't test this) print

  1
  hello world
  2

A mixin wrapper would be the next step down, with its methods coming
before the class methods. Making a 'super' call from a wrapper is going
in the same direction as the class super.

I can't think of a good way to say what I have in mind - "parent, child,
grandchild" doesn't work. It's more like "skeleton, body, clothes". :)

I did think of a downside... The original class would have to be
modified to have "include Mixin", whereas AspectR can layer across from
outside. There would also have to be a few support routines to implement
some of AOP's other ideas like pattern matching on method names.