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std::experimental::optional::operator->,std::experimental::optional::operator*(3) C++ Standard Libary std::experimental::optional::operator->,std::experimental::optional::operator*(3)

NAME

std::experimental::optional::operator->,std::experimental::optional::operator* - std::experimental::optional::operator->,std::experimental::optional::operator*

Synopsis


constexpr const T* operator->() const; (1) (library fundamentals TS)
constexpr T* operator->(); (1) (library fundamentals TS)
constexpr const T& operator*() const&; (2) (library fundamentals TS)
constexpr T& operator*() &; (2) (library fundamentals TS)
constexpr const T&& operator*() const&&; (2) (library fundamentals TS)
constexpr T&& operator*() &&; (2) (library fundamentals TS)


Accesses the contained value.


1) Returns a pointer to the contained value.
2) Returns a reference to the contained value.


The behavior is undefined if *this does not contain a value

Parameters


(none)

Return value


Pointer or reference to the contained value.

Exceptions


Throws nothing.

Notes


This operator does not check whether the optional contains a value. If checked
access is needed, value() or value_or() may be used.

Example

// Run this code


#include <experimental/optional>
#include <iostream>
#include <string>
using namespace std::literals;
int main()
{
std::experimental::optional<int> opt1 = 1;
std::cout << *opt1 << '\n';


std::experimental::optional<std::string> opt2 = "abc"s;
std::cout << opt2->size() << '\n';
}

Output:


1
3

See also


value returns the contained value
(public member function)
value_or returns the contained value if available, another value otherwise
(public member function)

2022.07.31 http://cppreference.com