Prototypical Objects on ruby

prototype.rb

class Prototype
  def new(member = {}, &block)
    prototype(member || {}, self,&block)
  end

  def respond_to?(name)
    return self if methods.include?(name.to_s)
    __proto__ = @proto.respond_to?(name)
    return __proto__ if __proto__
    false
  end

  def method_missing( _method, *_arg, &block)
    if __proto__ = @proto.respond_to?(_method)
      __proto__ = @proto if __proto__ == true
      __proto__.method(_method).call(*_arg,&block)
    else
      if _method.to_s[_method.to_s.length - 1].chr == '='
        instance_variable_set( "@#{_method.to_s[ 0..._method.to_s.length - 1]}", _arg[0])
        self.class.class_eval("attr_accessor :#{_method.to_s[ 0..._method.to_s.length - 1]}")
      else
        if block_given?
          self.class.class_eval do
            define_method( _method.to_sym, &block)
          end
        else
          raise NoMethodError
        end
      end
    end
  end
  
  attr_reader :proto
end
  
def prototype(member = {}, _proto_ = nil, &defs)
  _class = Class.new(Prototype)
  _class.class_eval(&defs) if block_given?
  instance = _class.new
  instance.instance_variable_set( :@proto, _proto_)
  (member || {}).each_pair do | key, val |
    instance.instance_variable_set( :"@#{key.to_s}", val)
    _class.class_eval("attr_accessor :#{key}")
  end
  instance
end

a = prototype({:foo => "foo" }, "String")

puts a.inspect