From: Robert Dober <robert.dober@...>
Date: 2006-11-05T03:18:40+09:00
Subject: Re: Redefining a class

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On 11/4/06, ara.t.howard@noaa.gov <ara.t.howard@noaa.gov> wrote:
>
> On Sat, 4 Nov 2006, Robert Dober wrote:
>
> > Hi all
> >
> > Recently we had a thread where we talked about redefining a class.
> > The usefuleness of that did not come into my mind before.
> >
> > Does somebody know a way to redefine a class (without the "already
> > initialized constant <ClassName>" warning)?
> > And if there is none, which I suspect, might it not be nice to have one?
>
>
>    c = Class.new{
>      def initialize
>        @x = 'foo'
>      end
>    }
>    o = c.new
>
>    c = Class.new{
>      def initialize
>        @x = 'bar'
>      end
>    }
>    o = c.new
>
> ;-)
>
>
> -a
> --
> my religion is very simple.  my religion is kindness. -- the dalai lama
>
>
Actually I am very disappointed that you cannot read my mind Ara ;) it would
be quite antipols to use
not constant classnames (wouldn't be there some warnings too BTW?)

class C...

C=Class.new...

works fine save for the warning I would like to get around

Here go some ideas:

(1) ruby does not insult you for constant redefinition if you assign a
reference to Class (arrrghh bad dangerous)
(2) allow an explicit syntax for redefining a class
     (2.a)  class A < B  *always* redefines the class Pro: Some Gurus expect
this behavior anyway :)

Cons: Quite implicit
     (2.b)  new class A                                               Pro:
Quite POLS and readable

Cons: "new" overloaded maybe use "redefine class A"
(3) some meta thingies
    (3.a) const_set does not warn anymore
    (3.b) Matz gives us a const_undefine for Christmas ;)

Ok what you think?

Robert

-- 
The reasonable man adapts himself to the world; the unreasonable one
persists in trying to adapt the world to himself. Therefore all progress
depends on the unreasonable man.

- George Bernard Shaw

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