From: "David A. Black" <dblack@...>
Date: 2008-10-03T20:58:44+09:00
Subject: Re: No warning for redefine

Hi --

On Fri, 3 Oct 2008, Han Holl wrote:

> Hi,
>
> Shouldn't the following:
>
> #!/usr/bin/ruby -w
>
> module Mixin
>  def function
>    puts 'Mixin'
>  end
> end
> include Mixin
> def function
>  puts 'Main'
> end
>
> function
> # end of demo.rb
>
> produce something like:
>
> demo.rb:9: warning: method redefined; discarding old function
>
> Behaviour now is to discard the mixed-in method silently.

It's not discarded; it's still there (in the module) and you can use
it with other classes, or reach it through 'super' in the override.
Discarding means you can never get to a method again:

   class C
     def m
     end
     def m   # Previous m is now completely uncallable
     end
   end


David

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