Почему использование «префиксной» нотации оператора- приводит к сбою разрешения перегрузки ⇐ C++

[Гость]

The following code snippet fails to compile:

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struct HasOperatorMinus {     int v;     HasOperatorMinus operator-(HasOperatorMinus o) { return operator-(this->v, o.v); } }; auto f(HasOperatorMinus a) {     return a - a; } 

https://godbolt.org/z/Kx1Kccfzs says

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:3:80: error: too many arguments to function call, expected single argument 'o', have 2 arguments     3 |     HasOperatorMinus operator-(HasOperatorMinus o) { return operator-(this->v, o.v); }       |                                                             ~~~~~~~~~          ^~~ :3:22: note: 'operator-' declared here     3 |     HasOperatorMinus operator-(HasOperatorMinus o) { return operator-(this->v, o.v); }       |                      ^         ~~~~~~~~~~~~~~~~~~ 

What the compiler says is that in the implementation

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operator-(this->v, o.v)

, overload resolution failed. I do not understand why the binary overload of

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operator-

for integers is hidden in this scenario.

Dear reader, please do not tell us that we can use the "infix" notation in the implementation. The question is about the difference between the prefix notation and the infix.


Источник: https://stackoverflow.com/questions/781 ... ion-failur