std::is_within_lifetime

 

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Defined in header <type_traits>
template< class T > consteval bool is_within_lifetime( const T* p ) noexcept;		(since C++26)

Determines whether the pointer p points to an object that is within its lifetime. During the evaluation of an expression E as a core constant expression, a call to is_within_lifetime is ill-formed unless p points to an object that is usable in constant expressions or whose complete object’s lifetime began within E.

Parameters

p

-

pointer to detect

Return value

true if pointer p points to an object that is within its lifetime; otherwise false.