From: Florian Gross <flgr@...>
Date: 2005-01-29T09:10:51+09:00
Subject: Re: Proc rebinding

Csaba Henk wrote:

> A Proc obejct carries its binding with itself (ie. is a closure), as it
> is well known. When @@hello was created, it did not know any @name. But
> then it was passed to define_method, and the resulting method "hello"
> can find @name in the instances. That is, ruby altered the bindings of
> (some kind of copy of) @@hello, and only after that has it been attached
> as a method. (Or rather, the binding is altered upon instantiation?)
> 
> [...]
> * Is it possible with EvilRuby?

Yes, EvilRuby has Proc#self= which will change the self-context of a 
block. Which might be a bad idea because Ruby might expect Procs to be 
immutable, but I've not experienced any oddities yet. If I'm not 
completely wrong this will however not change the scope of a proc 
meaning it will still refer to the surrounding variables. (So the result 
is a bit similar to using .instance_eval().)

Regarding methods: You can cheat there by using 
obj.method(:x).unbind.force_bind(other_obj) which is also available in a 
limited version in EvilRuby.