Just a note that I recently released a new gem, fast_forward, which adds support for delegation of all missing methods to another object, and does a bit of dynamic method generation to reduce overhead for subsequent calls. The API looks something like:

class Foo def some_foo_method "Hello" end end class Bar fast_forward_to :@foo def initialize @foo = Foo.new end end

(Note I could have used fast_forward_to :foo if there was an attr_reader for it)

Now, if I create a Bar instance, I can call Foo#some_foo_method transparently using
Bar#some_foo_method:

bar = Bar.new bar.some_foo_method => "Hello"

What’s cool with this setup is the fact that methods are added automatically to the delegating object when they’re invoked for the first time — future invocations don’t need to check up the object hierarchy and resort to method_missing:

bar = Bar.new bar.respond_to?(:some_foo_method) => false bar.some_foo_method => "Hello" bar.respond_to?(:some_foo_method) => true

fast_forward is a small library — but the concepts rolled into it have been pretty handy for me in recent projects.