gistfile1.txt

    def define_equivalent_method(methods)
      respond_to = []
      equivalent = []

      methods.each do |method|
        respond_to << "other.respond_to?(#{method.inspect})"
        equivalent << "#{method} == other.#{method}"
      end

      class_eval <<-RUBY, __FILE__, __LINE__ + 1
        def ==(other)
          return true if equal?(other)
          result = #{respond_to.join(' && ')} &&
          #{equivalent.join(' && ')}
          result
        end
      RUBY
    end