From: Martin Boese <boesemar@...>
Date: 2008-03-10T00:15:16+09:00
Subject: Re: Redefine a class with same name

Excellent! That's fine for me. I only have the case for a web framework of 
mine when using with fastcgi as different calls might use same class names 
which I can unregister now.

Thanks,
martin


On Sunday 09 March 2008 13:50:59 Rick DeNatale wrote:
> On 3/9/08, ts <decoux@moulon.inra.fr> wrote:
> > >>>>> "M" == Martin Boese <boesemar@gmx.de> writes:
> >
> >  M> Is there any way to to remove the definition of a class so I can
> > reuse its M> name? Like below I'd like to reuse the name 'A' but since
> > it's already M> defined with a different superclass I get a 'TypeError:
> > superclass mismatch M> for class A'.
> >
> >   Just remove the constant
> >
> >  M> class A < X
> >  M> end
> >
> >    Object.send(:remove_const, :A)
> >
> >  M> class A < Y
> >  M> end
>
> Keep in mind though, that this only removes the binding between the
> constant and the class, it doesn't actually allow you to change the
> old class, and any existing instances will still be instances of the
> old class not the new one:
>
> k$ irb
> irb(main):001:0> class A
> irb(main):002:1>   def foo
> irb(main):003:2>     end
> irb(main):004:1> end
> => nil
> irb(main):005:0> a = A.new
> => #<A:0x6e578>
> irb(main):006:0> a.foo
> => nil
> irb(main):007:0> Object.send(:remove_const, :A)
> => A
> irb(main):008:0> a.foo
> => nil
> irb(main):009:0> a.class
> => A
> irb(main):010:0> A
> NameError: uninitialized constant A
>         from (irb):10
> irb(main):011:0> class A
> irb(main):012:1> def bar
> irb(main):013:2> end
> irb(main):014:1> end
> => nil
> irb(main):015:0> a.bar
> NoMethodError: undefined method `bar' for #<A:0x6e578>
>         from (irb):15
> irb(main):016:0>