From: Joel VanderWerf <vjoel@...>
Date: 2005-07-28T02:57:33+09:00
Subject: Re: What's so special about operators, built-in classes and modules?

Very nice technique, but...

Ara.T.Howard wrote:
>   module M
>     module ClassMethods
>     end
>     module InstanceMethods
>     end
>     include InstanceMethods
>     self.extend ClassMethods
>     def self::included other
>       class << other
>         include InstanceMethods
          ^^^^^^^^^^^^^^^^^^^^^^^
This is redundant.
>       end
>       other.extend ClassMethods
>     end
>   end

For the newbies: In the old, old days (1.6 maybe), we had to use
#append_features instead of #included, and that did require explicitly
including the module. And sometimes we had to whack it with a dinosaur
bone to make it work.

Btw, the doc for append_features is unclear (as someone else on this
thread pointed out) about the difference between including a module and
adding methods:

------------------------------------------------- Module#append_features
     append_features(mod)   => mod
------------------------------------------------------------------------
     When this module is included in another, Ruby calls
     +append_features+ in this module, passing it the receiving module
     in _mod_. Ruby's default implementation is to add the constants,
     methods, and module variables of this module to _mod_ if this
     module has not already been added to _mod_ or one of its ancestors.
     See also +Module#include+.