运算符

运算符重载是通过 std::ops 中的特征实现的：

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Speaker Notes

 This slide should take about 10 minutes.

讨论点：

  • You could implement Add for &Point. In which situations is that useful?
    • 回答：Add:add 会耗用 self。如果您的运算符重载对象 （即类型 T）不是 Copy，建议您也为 &T 重载运算符。这可避免调用点上存在不必要的 克隆任务。
  • 为什么 Output 是关联类型？可将它用作该方法的类型形参吗？
    • Short answer: Function type parameters are controlled by the caller, but associated types (like Output) are controlled by the implementer of a trait.
  • 您可以针对两种不同类型实现 Add，例如， impl Add<(i32, i32)> for Point 会向 Point 中添加元组。