How can I invoke an overloaded () operator on the keyword this?

Question

The following works but feels ugly when I do the (*this)(5) part.

struct MyStruct
{
    void operator()(int a)
    {
        // Do something with "a"
    }

    void myFunc()
    {
        (*this)(5);
    }
};

I will need to overload the () operator and use it from within other class methods.

Answer 1

You have a few options:

• (*this)(5)

• this->operator()(5)

• or just operator()(5)

• Create a method that you call from within the operator(), e.g.:

  void do_work(int a) { /* ... */ }
  void operator()(int a) { do_work(a); }
  void myFunc() { do_work(5); }
  

Whichever you choose is just a matter of personal taste.

---

Just for fun, here are some more (ridiculous) options:

• std::invoke (mentioned in comments):

  std::invoke(&MyStruct::operator(), this, 5);
  

• mem_fn:

  auto call_op = std::mem_fn(&MyStruct::operator());
  call_op(this, 5);
  

• lambda:

  auto call_op = [this] (int a) { operator()(a); };
  call_op(5);
  

• bind_front

  auto call_op = std::bind_front(&MyStruct::operator(), this);
  call_op(5);