fast_forward 1.0.0

2007-05-14

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.