gistfile1.rb

  it "instance_eval" do
    class SomeClass
    end

    c = SomeClass.new
    c.instance_eval do
      def new_method
        "test"
      end
    end
    SomeClass.class_eval do
      def self.another_method
        "test2"
      end
    end

    c.new_method.should == "test"
    SomeClass.another_method.should == "test2"
  end