المشغلات (Operators)

Operator overloading is implemented via traits in std::ops:

XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX

Speaker Notes

This slide should take about 5 minutes.

Discussion points:

  • You could implement Add for &Point. In which situations is that useful?
    • Answer: Add:add consumes self. If type T for which you are overloading the operator is not Copy, you should consider overloading the operator for &T as well. This avoids unnecessary cloning on the call site.
  • Why is Output an associated type? Could it be made a type parameter of the method?
    • Short answer: Function type parameters are controlled by the caller, but associated types (like Output) are controlled by the implementer of a trait.
  • You could implement Add for two different types, e.g. impl Add<(i32, i32)> for Point would add a tuple to a Point.