ruby - 在模块前添加 ActiveSupport::Concern ？ ruby 2+

Question

Module Baz
   def foo
     super
     :baz
   end
end


Class A
   prepend Baz

   def foo
     :bar
   end
end

A.new.foo //works fine

现在如果我将我的模块转换为关注模块，它就不是......

module BazConcern
  extend ActiveSupport::Concern

  included do    
    def foo
      super
      :baz
    end
  end
end

那么我们如何在 ActiveSupport::Concern 中使用 prepend ？ 与 ruby​​ 2+

Answer 1

前面添加 ActiveSupport::Concern (Rails 6.1+)

Rails 6.1 添加了对 prepend 的支持与 ActiveSupport::Concern .

请参阅以下示例:

module Imposter
  extend ActiveSupport::Concern

  # Same as `included`, except only run when prepended.
  prepended do
    
  end
end

class Person
  prepend Imposter
end

还值得一提的是concerning还更新了:

class Person
  concerning :Imposter, prepend: true do

  end
end

来源:

• 指向相应 commit 的链接.

• Rails allows a module with extend ActiveSupport::Concern to be prepended .

• prepend和 concerning文档。