std::optional<T>::reset

#include <optional>
#include <iostream>

struct A {
    std::string s;
    A(std::string str) : s(std::move(str))  { std::cout << " \n"; }
    ~A() { std::cout << " \n"; }
    A(const A& o) : s(o.s) { std::cout << "  \n"; }
    A(A&& o) : s(std::move(o.s)) { std::cout << "  \n"; }
    A& operator=(const A& other) {
        s = other.s;
        std::cout << "  \n";
        return *this;
    }
    A& operator=(A&& other) {
        s = std::move(other.s);
        std::cout << "  \n";
        return *this;
    }
};

int main()
{
    std::cout << "  optional:\n";
    std::optional<A> opt;

    std::cout << "   :\n";
    opt = A("Lorem ipsum dolor sit amet, consectetur adipiscing elit nec.");

    std::cout << " optional:\n";
    opt.reset();
    std::cout << " \n";
}