From: dblack@...
Date: 2006-06-09T19:58:19+09:00
Subject: Re: Why the lack of mixing-in support for Class methods?

Hi --

On Fri, 9 Jun 2006, Logan Capaldo wrote:

>
> On Jun 8, 2006, at 10:25 PM, Yukihiro Matsumoto wrote:
>
>> Hi,
>> 
>> In message "Re: Why the lack of mixing-in support for Class methods?"
>>    on Fri, 9 Jun 2006 09:22:55 +0900, transfire@gmail.com writes:
>> 
>> |Considering the above (which by the way should also have an 'include
>> |Beanable'), a notation that has some similarity and is available for
>> |use:
>> |
>> |   class Beanbag
>> |     self << Beanable
>> |   end
>> 
>> I like this more than others, but I worry about that this is less
>> descriptive than other at the same time.  For example, how one can
>> know whether "include" does not injects module methods, where "<<"
>> does.
>>
>> 							matz.
>> 
>
> well we have class << self, which involves singleton methods
>
> why not
> class Beanbag
> include << Beanable
> end
>
> which would also involve singleton methods?

I'm not sure << really evokes "connected in some way with singleton
methods", though.  Then again, I'm not sure what's wrong with
"extend", so I'm probably a bit out of the loop on this discussion.

> (Of course then include has to be a keyword (or "include <<" at
> least))

Not necessarily:

class MyModule
   def initialize
     @list = []
   end

   def include(*args)
     if args.size.zero?
       @list
     else
       @list.concat(args)
     end
   end
end

m = MyModule.new
m.instance_eval {

   include "a", "b"
   include << "c"

   p @list      # ["a", "b", "c"]
}


David

-- 
David A. Black (dblack@wobblini.net)
* Ruby Power and Light, LLC (http://www.rubypowerandlight.com)
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