Ruby:扩展自我 [英] Ruby: extend self

问题描述

在Ruby中，我了解extend的基本思想.然而，这段代码中发生了什么?具体来说，extend 做了什么?它只是将实例方法变成类方法的便捷方式吗?为什么要这样做而不是从一开始就指定类方法?

In Ruby, I understand the basic idea of extend. However, what's happening in this segment of code? Specifically, what does extend do? Is it just a convenient way of making the instance methods into class methods? Why would you do it this way rather than specifying class methods from the beginning?

module Rake
  include Test::Unit::Assertions

  def run_tests # etc.
  end

  # what does the next line do?
  extend self
end

推荐答案

将实例方法变成类方法是一种便捷的方式.但您也可以将其用作 更高效单身.

It is a convenient way to make instance methods into class methods. But you can also use it as a more efficient singleton.

这篇关于Ruby:扩展自我的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！