// The following types are collectively called implicit-lifetime types:// * scalar types://     * arithmetic types//     * enumeration types//     * pointer types//     * pointer-to-member types//     * std::nullptr_t// * implicit-lifetime class types//     * is an aggregate whose destructor is not user-provided//     * has at least one trivial eligible constructor and a trivial,//       non-deleted destructor// * array types// * cv-qualified versions of these types.#include <type_traits> static_assert(std::is_implicit_lifetime_v<int>);// arithmetic type is a scalar typestatic_assert(std::is_implicit_lifetime_v<constint>);// cv-qualified a scalar type enum E{ e};static_assert(std::is_implicit_lifetime_v<E>);// enumeration type is a scalar typestatic_assert(std::is_implicit_lifetime_v<int*>);// pointer type is a scalar typestatic_assert(std::is_implicit_lifetime_v<std::nullptr_t>);// scalar type struct S{int x, y;};// S is an implicit-lifetime class: an aggregate without user-provided destructorstatic_assert(std::is_implicit_lifetime_v<S>); static_assert(std::is_implicit_lifetime_v<int S::*>);// pointer-to-member struct X{ ~X()= delete;};// X is not implicit-lifetime class due to deleted destructorstatic_assert(!std::is_implicit_lifetime_v<X>); static_assert(std::is_implicit_lifetime_v<int[8]>);// array typestatic_assert(std::is_implicit_lifetime_v<volatileint[8]>);// cv-qualified array type int main(){}