Alternative to https://github.com/michaelfairley/method_decorators

a_rationale.md

No method_added hook implementation leads to proper working with include'ed methods.

Use prepend from Ruby 2.0. Decorators should return Modules as results of calling new:

class Memoize
  def self.new(method)
    m = Module.new
    m.define_method(method) do
      # memoization logic goes here.
      # use `super` to call original method.
    end
    m
  end
end

example.rb

class ExternalService
  def request
    # ...
  end
  prepend Retry.new(3, :request)

  module Response
    def response
      # ...
    end
  end
  include Response
  prepend Memoize.new(:response)
end

Included methods should work fine in my lib (assuming that the decoration was done inside the module itself). Have you run into problems doing that, or are you focused only on the includer itself doing the decoration?

(I really like the simplicity of this version.)

@michaelfairley - I was just focused on the case when the includer is doing the decoration. The simplicity of this version is possible only due to powerful nature of prepend which is a new brother of our beloved include. I can't wait to see what Ruby community is going to do with it.