C++

Reference

<functional>

reference_wrapper

public member function
<functional>

std::reference_wrapper::operator type&

operator type&() const noexcept;
Cast to reference
Returns a reference to the referred element.

type is a member type describing the referred type (it is an alias of the class template parameter, T).

This returns the same as member get.

Parameters

none

Return value

The referred element.

type is a member type describing the referred type (it is an alias of the class template parameter, T).

Example

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// reference_wrapper::operator type&
#include <iostream>     // std::cout
#include <functional>   // std::reference_wrapper

int main () {
  int foo;

  std::reference_wrapper<int> wrap (foo);

  static_cast<int&>(wrap) = 10;
  int& bar = wrap;
  ++bar;

  std::cout << foo << '\n';

  return 0;
}

Output:
11


Data races

The object is accessed.
The reference returned can be used to access or modify element.

Exception safety

No-throw guarantee: this member function never throws exceptions.

See also

reference_wrapper::get
Access element (public member function)
reference_wrapper::operator()
Access element (functional form) (public member function)