std::experimental::optional<T>::operator->, std::experimental::optional<T>::operator*
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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
| returns the contained value (public member function) | |
| returns the contained value if available, another value otherwise (public member function) |