< cpp‎ | utility‎ | optional
Utilities library
Language support
Type support (basic types, RTTI)
Library feature-test macros (C++20)
Dynamic memory management
Program utilities
Coroutine support (C++20)
Variadic functions
Debugging support
Three-way comparison
General utilities
Date and time
Function objects
Formatting library (C++20)
Relational operators (deprecated in C++20)
Integer comparison functions
Swap and type operations
Common vocabulary types
Elementary string conversions

(since C++17)
(constexpr since C++20)

If the object contains a value and the type T is not trivially destructible (see std::is_trivially_destructible), destroys the contained value by calling its destructor, as if by value().T::~T().

Otherwise, does nothing.

[edit] Notes

If T is trivially-destructible, then this destructor is also trivial, so std::optional<T> is also trivially-destructible.

Feature-test macro Value Std Feature
__cpp_lib_optional 202106L (C++20)
Fully constexpr

[edit] Defect reports

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 not constexpr while non-trivial destructors can be constexpr in C++20 made constexpr