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| Member functions | ||||
optional::~optional | ||||
| Observers | ||||
| Iterators | ||||
(C++26) | ||||
(C++26) | ||||
| Monadic operations | ||||
(C++23) | ||||
(C++23) | ||||
(C++23) | ||||
| Modifiers | ||||
| Non-member functions | ||||
| Deduction guides | ||||
| Helper classes | ||||
| Helper objects | ||||
~optional(); | (since C++17) (constexpr since C++20) | |
If the object contains a value and the typeT is not trivially destructible (seestd::is_trivially_destructible), destroys the contained value by calling its destructor, as if byvalue().T::~T().
Otherwise, does nothing.
IfT is trivially-destructible, then this destructor is also trivial, sostd::optional<T> is also trivially-destructible.
| Feature-test macro | Value | Std | Feature |
|---|---|---|---|
__cpp_lib_optional | 202106L | (C++20) (DR20) | Fullyconstexpr |
The following behavior-changing defect reports were applied retroactively to previously published C++ standards.
| DR | Applied to | Behavior as published | Correct behavior |
|---|---|---|---|
| P2231R1 | C++20 | the destructor was notconstexpr while non-trivial destructors can beconstexpr in C++20 | madeconstexpr |
