[ruby-talk:00540] Re: A new discussion topic ;-)

Hi,

From: Clemens Hintze <[e-mail]>
Subject: [ruby-talk:00539] A new discussion topic ;-)
Date: Sun, 1 Aug 1999 12:41:15 +0200

[snip]
>
> What do you think?
> 
> I think the Self approach is a great idea. There are no classes
> anymore. Only objects.  Every object could be used to build
> instances. Objects without inheriting from others, could be seen as
> Ruby `Modules'. Objects, inheriting from `Cloneable' could be used
> directly, but could also build new instances like a class in Ruby.
> 
> As I have already said, it is not a real proposal. But I would like to
> know, what would you think about a language with Ruby's syntax but a
> OOP concept like the explained above. Would you like such a language?

In Ruby, we use class and Mix-in structures.  Now I get used to love
it, and so can't imagine whether or not Self's way is suit for me.
But there is one thing I had thought of, that is `temporal extend'.

In Self, objects have instance variables, and methods wrap them --I
feel they are separated--.  In contrast with Self, Ruby's methods and
instance vars are very strongly connected, I feel, except for the case
of Mix-in modules.

This reminds me the temporal extend:


class Self ; def initialize(&blk); instance_eval(&blk) if blk end end

module Foo
  def say_hello(name); print "#{@greeting} #{name}\n" end
end

bar = Self.new do
  @greeting = "Hello"
  class << self
    def say_hello!(name)
      extend(Foo)
      say_hello(name)
    end
    def say_hello?(name)
      temporal_extend(Foo) do
	say_hello(name)
      end
    end
  end
end

This is a little like Self's way, isn't it... Now `extend' is
available in Ruby, but it leaves side effects. Methods are overrided.
So I thought of temporal one, leaves no side effects.

Sorry, maybe your point is classes, and this is not.  However, in the
case `temporal extend' is in need, Self's way is also useful, I think.
(and vice versa ?)

Thanks,
--
sorry for my broken english
best regards
Kazuhiro HIWADA ([e-mail])