From: Jean-Hugues ROBERT <jean_hugues_robert@...>
Date: 2002-06-13T19:26:00+09:00
Subject: Re: Trick or Bug?

At 07:48 13/06/2002 +0900, you wrote:
>On Wednesday 12 June 2002 01:02 pm, Hal E. Fulton wrote:
> > ----- Original Message -----
> > From: "Nikodemus Siivola" <tsiivola@cc.hut.fi>
> > To: "ruby-talk ML" <ruby-talk@ruby-lang.org>
> > Sent: Wednesday, June 12, 2002 5:26 AM
> > Subject: Trick or Bug?
> >
> > > All this talk of block local variables reminded me of a funny trick...
> > >
> > > As you know, receivers in ruby cannot change their class? No become, etc.
> > > Right?
> > >
> > > Wrong:
> > >
> > > #!/usr/bin/env ruby
> > > a = proc { a = 1 }
> > > puts "a is a #{a.class}"
> > > a.call
> > > puts "a is a #{a.class}"
> >
> > Clever, but not correct, I think.
> > You've just pointed 'a' to a
> > different object, not changed the
> > class of the original object.
> >
> > As I understand 'become' in Smalltalk
> > (and I don't really) doesn't it
> > operate on an object?
>
>I never used it.  But if I remember correctly it changes ALL references to 
>the
>old object to a new object.
> >
> > Hal Fulton

ALL, that's pretty frightening !

I guess that most of the time when I was referring to "become" so far
I should have used "become_a" instead. 'a.become_a X; assert a.type == X'

Thanks for the clarification.

Yours,

Jean-Hugues


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