From: ts <decoux@...>
Date: 2003-03-26T18:54:58+09:00
Subject: Re: question about include and modules

>>>>> "M" == Mauricio =?iso-8859-1?Q?Fern=E1ndez?= <Mauricio> writes:

M> Is this because array.c uses rb_include_module instead of
M> rb_mod_include?
 
 No, the problem is with the internal of ruby. When you add a module in
 another module, you must re-call include to force ruby to update the
 `path' of the class.

 When you write

    class A
       include B
    end

 The `path' for A is

    A ==> [B] ==> Object ==> [Kernel]

 where [B] is a proxy class which refer to the module B

 Now with

   module B
      include C
   end

   class A
      include B
   end

 ruby will do

    A ==> [B] ==> [C] ==> Object ==> [Kernel]

 i.e. the path is modified when ruby *make* the include

 If you include another module in B, ruby will not update the path for A
 (it has lost the information that B was included in A)


Guy Decoux