migration-down.rb

class AClassicPattern < ActiveRecord::Migration

  def self.up
     begin
       try
     rescue
       raise ObiWan, "You're my only hope."
     end

  end

  def self.down
    raise NotImplementedError, "There is no undo"
  end

  def self.try
    raise NotImplementedError, "Do or do not.  There is no 'try.'"
    ghost = class << obj; self; end
    ghost.remove_method :try
  end
  
end