From: Yusuke ENDOH <mame@...>
Date: 2009-09-01T04:22:24+09:00
Subject: [ruby-core:25234] Re: Module#prepend and Array#prepend

2009/9/1 Yukihiro Matsumoto <matz@ruby-lang.org>:
> Hi,
>
> In message "Re: [ruby-core:25228] Re: Module#prepend and Array#prepend"
>    on Tue, 1 Sep 2009 03:24:30 +0900, Yusuke ENDOH <mame@tsg.ne.jp> writes:
>
> |However, I think that module inclusion is not such a patching tool;
> |open class is.
>
> |Then, I guess that what we really need is a method wrapping feature:
> |
> |  class Person
> |    refine_method(:speak) do |old_method, words|
> |      # old_method is a Method of original definition
> |      old_method.call("#{ words }!")
> |    end
> |  end
> |  Person.new.speak("matz") #=> "matz!"
>
> Can you elaborate why you think module inclusion is not such a
> patching tool,

I have understood that module mix-in is just adding a concern because,
as far as I know, the built-in modules (i.e., Comparable, Enumerable,
etc.) merely add methods and do not modify existing methods of original
class.


> and the above "refine_method" is sought solution than
> Module#prepend?

I thought:

- we should use open class or reflection to redefine an existing method,

- but it is burdensome to redefine a method with using its original
  behavior,

- then, the method to do it may be helpful.

-- 
Yusuke ENDOH <mame@tsg.ne.jp>