std::variant<Types...>::~variant

If valueless_by_exception() is true, does nothing. Otherwise, destroys the currently contained object.

# Declarations

~variant();

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

# Notes

Feature-test macro Value Std Feature __cpp_lib_variant 202106L (C++20)(DR) Fully constexpr std::variant

# Example

#include <cstdio>
#include <variant>
 
int main()
{
    struct X { ~X() { puts("X::~X();"); } };
    struct Y { ~Y() { puts("Y::~Y();"); } };
 
    {
        puts("entering block #1");
        std::variant<X,Y> var;
        puts("leaving block #1");
    }
 
    {
        puts("entering block #2");
        std::variant<X,Y> var{ std::in_place_index_t<1>{} }; // constructs var(Y)
        puts("leaving block #2");
    }
}

# Defect reports

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