prevent-recursion.rb

  def self.prevent_recursion(method_name)
    flag_name = "in:#{name}##{method_name}"
    original = instance_method(method_name)
    define_method(method_name) do |*args|
      if Thread.current[flag_name]
        return
      else
        begin
          Thread.current[flag_name] = true
          original.bind(self).call(*args)
        ensure
          Thread.current[flag_name] = nil
        end
      end
    end
  end