Adding a new method to the Array class

问题

I have a new requirement on Array object. So I need to add my own method to built-in Array class.

How do I add a new method so that whatever Array object I create, it will also have my instance method?

回答1:

Use Ruby Open Classes:

class Array
  def mymethod
    #implementation
  end
end

回答2:

The other answers basically show you can add a method to the class by redefining the class, just to add to that, an example could be like this:

class Array
    def third
        size > 2 ? self[2] : nil
    end
end

a = [1, 2, 3, 4, 5]

puts a.third

来源：https://stackoverflow.com/questions/17858816/adding-a-new-method-to-the-array-class