From: "David A. Black" <dblack@...>
Date: 2004-12-15T22:06:03+09:00
Subject: Re: initialize always

Hi --

On Wed, 15 Dec 2004, Robert Klemme wrote:

> Finally today I found a sheet of paper while cleaning my desk.  (It's good
> to do that once in a while. :-))
>
> It hadn't made it to an RCR though.  The suggestion would have been this:
> if a Module defines method initialize without an argument list then
> implicitely change that to be initialise(*a,&b) and implicitely add super
> as first line in the method: Thus
>
> module Foo
>  def initialize
>    @bar = 0
>  end
> end
>
> becomes
>
> module Foo
>  def initialize(*a,&b)
>    super
>    @bar = 0
>  end
> end
>
> Note: identifiers for arguments and block may have to be generated to be
> unique.
>
> All other cases (i.e. combinations of with / without argument list and
> with / without occurrence of "super" in the body of this method) should
> remain unchanged, because they would cause too much hassle.
>
> Pro: this change allows for easy initialization of instance variables
> needed by modules even if there are multiple modules included:
>
> class Base
>  def initialize(x)
>    @x = x
>   end
> end
>
> class Test < Base
>  include Foo
>  include Bar
>
>  def initialize(a, b)
>     super(a)
>     @b = b
>  end
> end
>
> What do others think?

My initial reaction is that it's too magic for my taste... too much
written in "invisible ink".  If I write: def meth; ...; end then I
want it to fail if it's called with arguments.   But I'm also not
understanding the 'pro' point very thoroughly, or maybe I've just
never had this problem.  I think I'm just being thick, but can you
explain a little more how/when/why this would be useful?


David

-- 
David A. Black
dblack@wobblini.net