From: Eric Mahurin <eric_mahurin@...>
Date: 2005-05-07T05:01:54+09:00
Subject: Re: object reference handle (like perl's reference to scalar)

I tried this out and it doesn't seem to do anything.  I did a
require "delegate" followed by the code below.  Could you give
a concrete example - working on mutable (string or array) and
immediate obects (i.e. Fixnum).  Even if you get this to work
on the mutable objects, I don't see it working on the immediate
objects.

> --- dave.burt@gmail.com wrote:
> > To me, this looks more Rubyish. Is there some benefit I'm
> > missing in
> > your pulling variable names out of the closure like you do
> > there, Eric?
> > If it's all the same, why not just have the object pass
> > itself into a
> > reference constructor (as my Object#ref does)?
> > # ref.rb
> > #
> > # For those times you need an extra level of indirection.
> > #
> > # Example:
> > #   def swap(a,b)
> > #     tmp = a[]
> > #     a[] = b[]
> > #     b[] = tmp
> > #   end
> > #
> > #   swap(x.ref, y.ref) # convert x and y to references then
> > swap them
> > #
> > Ref = DelegateClass(Object) unless Object.const_defined?
> :Ref
> > class Ref
> >   # Dereference (get the referred-to value)
> >   alias deref __getobj__
> >   # Call with no index to dereference
> >   def [](*args)
> >     if args.empty?
> >       __getobj__
> >     else
> >       super
> >     end
> >   end
> >   # Set value (change the reference to point at something
> > else)
> >   def ref=(val) __setobj__(val) end
> >   # Call with no index to assign a new value
> >   def []=(*args)
> >     if args.size == 1
> >       __setobj__(args[0])
> >     else
> >       super
> >     end
> >   end
> > end
> > class Object
> >   # Make a reference
> >   def ref
> >     Ref.new(self)
> >   end
> > end



		
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