Question

有时我会看到这样的代码：

module Elite

    module App
        def app
            'run app'
        end
    end

    module Base
        def base
            'base module'
        end
    end

    class Application
        include Elite::Base #Include variant A
        include ::Elite::App #Include variant B

        def initialize(str=nil) 
            puts "Initialized with #{str}"
            puts "Is respond to base?: #{base if self.respond_to?(:base)}"
            puts "Is respond to app?: #{app if self.respond_to?(:app)}"

        end
    end

    class Store < ::Elite::Application

        def initialize(str=nil)
            super #Goes to Application init
        end
    end
end

elite = Elite::Store.new(:hello)

但我不明白class Store < ::Elite::Application和class Store < Elite::Application或include Elite::Base和include ::Elite::App之间的区别它只是编码风格，还是它的不同之处？

课程/模块之前::做了什么？ ::类/模块的clean名称空间（模块名称）？由于class Store < Application有效，但不是：class Store < ::Application。请告诉我有什么区别......谢谢！

Answer 1

＆＃39; ::＆＃39;是基础（全局）范围运算符。

所以＆＃39; ::应用程序＆＃39;引用基础应用程序作为＆＃39;应用程序＆＃39;引用当前范围内的应用程序。

例如

class Application # Class 1
end

class Smile
  class Application # Class 2
  end

  ::Application # references class 1
  Application # references class 2 (The application in my current scope)
end

理解使用“::”的Ruby代码

1 个答案: