std::optional::operator->, std::optional::operator*
From cppreference.com
| constexpr const T* operator->() const; |
(1) | (since C++17) |
| constexpr T* operator->(); |
(1) | (since C++17) |
| constexpr const T& operator*() const&; |
(2) | (since C++17) |
| constexpr T& operator*() &; |
(2) | (since C++17) |
| constexpr const T&& operator*() const&&; |
(2) | (since C++17) |
| constexpr T&& operator*() &&; |
(2) | (since C++17) |
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
(none)
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 <optional> #include <iostream> #include <string> int main() { using namespace std::string_literals; std::optional<int> opt1 = 1; std::cout << *opt1 << '\n'; std::optional<std::string> opt2 = "abc"s; std::cout << opt2->size() << '\n'; }
Output:
1 3
See also
| returns the contained value (public member function) | |
| returns the contained value if available, another value otherwise (public member function) |