def define_method(id, prototype)
      m = Method.new(id)
      m.from_prototype(prototype)
      define(m)
    end
def define_method(id, prototype)
      m = Method.new(id)
      m.from_prototype(prototype)
      define(m)
    end
Defines a method with name _id_ and a given _prototype_ in the
 interface.