forwardable_mixin

🔗 Delegation with the Forwardable Module

Forwardable lets you delegate selected methods to an internal object cleanly, avoiding boilerplate forwarding methods.

require 'forwardable'

module Trackable
  extend Forwardable
  def_delegators :@delegatee, :start, :stop

  def initialize(delegatee)
    @delegatee = delegatee
  end
end

class Engine
  def start; puts "Engine started" end
  def stop;  puts "Engine stopped"  end
end

class Vehicle
  include Trackable
end

Vehicle.new(Engine.new).start # => "Engine started"

Use def_delegators for multiple methods or def_delegator for single ones.