From: ts <decoux@...>
Date: 2002-04-01T21:40:23+09:00
Subject: Re: re-extending object

>>>>> "E" == Ed Sinjiashvili <edsin@swes.saren.ru> writes:

E> Yes, I've seen this in rb_include_module. But if you look at *my*
E> stupid.rb in the previous message :), you'll see that after extending
E> object with B and C, I can't reach neither of A methods. So
E> effectively A is not object's ancestor anymore.

 Here your example

 a = Object.new   # at this step you have
                  #   Object

 a.extend A       # ruby extend the object, and add an included class
                  #   [A] ==> Object

 a.extend B       # same with B
                  #   [B] ==> [A] ==> Object

 a.extend C       # same with C
                  #   [C] ==> [B] ==> [A] ==> Object

 a.extend A       # ruby search in the superclass and it found [A]
                  # i.e. the included class which make reference to Module A
                  # it don't try to include it and you still have
                  #   [C] ==> [B] ==> [A] ==> Object


 When you call a.a() it find C#a before A#a
               a.b()         B#b        A#b

E> Is there any way to #unextend A from the object so I could #extend it
E> with A again? I tried to use #remove_const to no avail.

 Not really sure, but I think that it's possible only in C


Guy Decoux