From: David Alan Black <dblack@...>
Date: 2002-04-12T21:50:38+09:00
Subject: Re: Idea for a new shorthand

Hi --

On Fri, 12 Apr 2002, Hal E. Fulton wrote:

> Do you see where I'm going? I propose a special
> name "prior" that will automatically refer to the
> prior definition of any method that is being replaced.
> No aliases will be necessary.
>
>     def system_method
>       if today == Sunday
>         # Do some stuff...
>       end
>       prior
>     end
>
> What do you think?

I've always thought of super as a Y-axis thing, and alias as an X-axis
thing.  I'm not sure whether they can be combined into one thing,
without some loss.  Here's a rather contrived example:

  class Thing < String
    alias :oldsplit :split
    def split(*sep)
      puts "New split"
      oldsplit(*sep)
    end
  end

  class Thing
    alias :othersplit :split
    def split(*sep)
      line = gets
      if /o/.match(line)
	othersplit(*sep)
      else
	super
      end
    end
  end

  str = Thing.new("this is a string")
  p str.split

I'm not sure how you could replace both super and alias with prior,
and still be able to do this kind of perpendicular branching (either
up the hierarchy, or sideways to the aliased "sibling" method).


David

-- 
David Alan Black
home: dblack@candle.superlink.net
work: blackdav@shu.edu
Web:  http://pirate.shu.edu/~blackdav