From: Robert Dober <robert.dober@...>
Date: 2007-06-03T06:55:24+09:00
Subject: Re: nested methods don't really exist?!

On 6/2/07, dblack@wobblini.net <dblack@wobblini.net> wrote:
> Hi --
>
> On Sun, 3 Jun 2007, Robert Dober wrote:
>
> > On 6/2/07, dblack@wobblini.net <dblack@wobblini.net> wrote:
> >> Trans wrote:
> >>
> >> >  module N
> >> >    def a
> >> >      def b
> >> >        "foo"
> >> >      end
> >> >    end
> >> >  end
> >> >
> >> >  class X
> >> >    include N
> >> >  end
> >> >
> >> >  X.new.a
> >> >
> >> > Currently we get:
> >> >
> >> >  N.instance_methods(false)  #=> ["a", "b"]
> >> >  X.instance_methods(false)  #=> []
> >> >
> >> > But why isn't it:
> >> >
> >> >  N.instance_methods(false)  #=> ["a"]
> >> >  X.instance_methods(false)  #=> ["b"]
> >>
> >> I'll give a modified version of my original answer.  If the default is
> >> to put the inner def in the same context as the outer def, then the
> >> simplest case (no change in context) has the simplest syntax, and it
> >> goes from there.  If the default is to put it in the context of
> >> self.class at the time of execution, then getting it into the flat
> >> context would require more effort.
> >>
> >> So I think it just keeps the semantics congruent with the syntax, or
> >> something.  One case or the other is going to require class_eval or
> >> equivalent, so I guess having the default case be the one where
> >> there's no automatic context-switching just keeps it more simple.
> >
> > This seems however to be the first case I ever have seen where the
> > Proxy of the Mixin is not transparent any more.
>
> How about constants:
>
>    module M
>      A = 1
>      def a
>        puts A
>      end
>    end
>
>    class C
>      include M
>      A = 2
>    end
>
>    C.new.a     # 1
>
> I think def is considered to be part of the business of the module
> where it's physically located, kind of in a constant way.
>
>
> David
>
Ah thanks, I was not aware of this case.

Robert
> --
> Q. What is THE Ruby book for Rails developers?
> A. RUBY FOR RAILS by David A. Black (http://www.manning.com/black)
>     (See what readers are saying!  http://www.rubypal.com/r4rrevs.pdf)
> Q. Where can I get Ruby/Rails on-site training, consulting, coaching?
> A. Ruby Power and Light, LLC (http://www.rubypal.com)
>
>


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