state_pattern_with_micromachine.rb

require 'state_pattern'

class Stop < StatePattern::State
  def next
    sleep 3
    transition_to(Go)
  end

  def color
    "Red"
  end
end

class Go < StatePattern::State
  def next
    sleep 2
    transition_to(Caution)
  end

  def color
    "Green"
  end
end

class Caution < StatePattern::State
  def next
    sleep 1
    transition_to(Stop)
  end

  def color
    "Amber"
  end
end

class TrafficSemaphore
  include StatePattern
  set_initial_state Stop
end

semaphore = TrafficSemaphore.new

loop do
  puts semaphore.color
  semaphore.next
end