包括两个具有相同方法名称的Ruby mixin

Question

这是怎么回事：

module Sounds
  def dog
    "bark"
  end
end

module Noises
  def dog
    "woof"
  end
end

class Animals
  include Sounds
  include Noises
end

x = Animals.new
x.dog # Returns "woof", as I expected

class Animals
  include Sounds
end

x.dog # Still returns "woof" for some reason -- shouldn't it be bark?

y = Animals.new
y.dog # Also returns "woof" for some reason -- shouldn't it be bark?

Answer 1

一旦你加入了一个模块，我不确定它是否会被再次包含在内。它可能会被列为已包含，因此忽略重复操作。

如果你需要这样做，这确实很奇怪，你可能需要通过创建一个包含目标模块的模块（甚至是一个临时模块）来伪造Ruby，然后再包含那个模块。