From: Logan Capaldo <logancapaldo@...>
Date: 2006-08-18T10:24:19+09:00
Subject: Re: using a module at the toplevel doesn't work


On Aug 17, 2006, at 3:24 PM, Pit Capitain wrote:

> Trans schrieb:
>> Unfortuately when I use this to make a Rake command-line emulator I
>> want to use the module at the toplevel and can't.
>
> Tom, I think I still don't get what your problem is. If you want to  
> use a module at the toplevel just include it in Object.
>
> The module:
>
>   module M
>     def val *args
>       if args.empty?
>         @val
>       else
>         @val = args[ 0 ]
>       end
>     end
>   end
>
> I used some instance variables here, because you wrote about them  
> in the answer to Matz.
>
> Make it available at the toplevel (and everywhere else):
>
>   class Object
>     include M
>   end
>
>   p val         # => nil
>   val  "main"
>   p val         # => "main"
>
> It's also available at the class level:
>
>   class Q
>     p val       # => nil
>     val "Q"
>     p val       # => "Q"
>   end
>
> HTH
>
> Regards,
> Pit
>

You are over simplifying Trans.'s problem. He wants dynamic generated  
methods scoped to a module, or optionally scoped to the top level.  
You can't use #define_method at the top level because instances don't  
respond to it. You can't use the toplevel singleton class as I  
suggested because a) it's a pain in the neck and b) it doesn't  
inherit the right way.


Trans, what about:

# Warning evilness ensuing:

def main.define_method(*args, &block)
   Kernel.module_eval{ define_method(*args, &block) }
end