From: Pit Capitain <pit@...>
Date: 2006-07-13T05:04:10+09:00
Subject: Re: [ANN] prototype-0.0.0

ara.t.howard@noaa.gov schrieb:
> 
> NAME
> 
>   prototype.rb
> 
> (...)
> 
> comments and patches welcome!

Great idea, and a nice syntax, Ara. Here's another implementation that isn't as 
efficient, but more "dynamic" than yours:

   module Prototype

     def self.new parent = nil, &blk
       mod = Module.new do

         include parent if parent
         extend self

         def clone
           Prototype.new self
         end

         def method_missing name, *args
           ivar = "@#{name}"
           case args.size
           when 0
             obj = ancestors.find { |m| m.instance_variables.include? ivar }
             if obj
               obj.instance_variable_get ivar
             else
               super
             end
           when 1
             instance_variable_set ivar, args.first
           else
             super
           end
         end

         def do &blk
           module_eval( &blk ) if blk
         end

       end
       mod.do( &blk )
       mod
     end

   end

It allows things like:

   Obj = Prototype.new {
     v 42
     def show; p v end
   }
   Obj.show  # => 42

   Cld = Obj.clone
   Cld.show  # => 42

   Cld.v 45
   Cld.show  # => 45
   Obj.show  # => 42

   Obj.do {
     x "x"
     def m; p x; end
   }
   Obj.m  # => "x"
   Cld.m  # => "x"

Regards,
Pit