From: ara.t.howard@...
Date: 2006-06-13T12:00:01+09:00
Subject: Re: How to invoke a run method???

On Tue, 13 Jun 2006, Eric Armstrong wrote:

> This is pretty ridiculous, but I have tried
> virtually every combination of class and module
> definitions that I can think of, all without
> success:
>
> I started with an old Post by Ara Howard:
> http://blade.nagaokaut.ac.jp/cgi-bin/scat.rb/ruby/ruby-talk/193039
>
> module Foo
>  class Main
>    ...
>  end
> end
> Foo::Main.run(ARGV, ENV) if __FILE__ == $0

   Foo::Main.new.run(ARGV, ENV) if __FILE__ == $0
             ^^^
             ^^^
             ^^^

> Then I found the ERB program at
> http://stuff.mit.edu/afs/sipb/project/ruby-lang/bin/erb
>
> That one reverses class & module:
>
> class ERB
>  module Main
>    def run

      def self.run

>      puts "Running"
>    end
>  end
> end
> Foo::Main.run if __FILE__ == $0



> What the heck is wrong with this picture?
> (thanks in advance)

in both situations you are reversing the notion of class/module and instance
methods.  in the first case you call a class method when it should be an
instance method, in the second you define an instance methods and then try to
call a class method.

   module M
     def self.foo
       'this is a class/module method'
     end
     def bar
       'this is an instance method'
     end
   end

we can do

   M.foo

   class C
     include M
   end

   C.new.bar



alternatively we can have

   class C
     def self.foo
       'this is a class/module method'
     end
     def bar
       'this is an instance method'
     end
   end

and do

   C.foo

   C.new.bar

make sense?

-a
-- 
suffering increases your inner strength.  also, the wishing for suffering
makes the suffering disappear.
- h.h. the 14th dali lama