std::experimental::optional::operator->, std::experimental::optional::operator*
From cppreference.com
< cpp | experimental | optional
constexpr const T* operator->() const;
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(1) | (library fundamentals TS) |
constexpr T* operator->();
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(1) | (library fundamentals TS) |
constexpr const T& operator*() const&;
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(2) | (library fundamentals TS) |
constexpr T& operator*() &;
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(2) | (library fundamentals TS) |
constexpr const T&& operator*() const&&;
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(2) | (library fundamentals TS) |
constexpr T&& operator*() &&;
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(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
Contents |
[edit] Parameters
(none)
[edit] Return value
Pointer or reference to the contained value.
[edit] Exceptions
(none)
[edit] Notes
This operator does not check whether the optional contains a value. If checked access is needed, value() or value_or() may be used.
[edit] 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
[edit] See also
returns the contained value (public member function) |
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returns the contained value if available, another value otherwise (public member function) |