From cppreference.com
template<classT>structis_pointer;(since C++11)std::is_pointer is a
.
Checks whether T is a
(including pointer to void, but excluding pointer to member) or a
version thereof. Provides the member constant value which is equal to true, if T is an object/function pointer type. Otherwise, value is equal to false.
If the program adds specializations for std::is_pointer or std::is_pointer_v, the behavior is undefined.
Template parameters
T - a type to check Helper variable template
template<classT>constexprboolis_pointer_v=is_pointer<T>::value;(since C++17)Inherited from
Member constants
value
[static]
true if T is a pointer type, false otherwise
(public static member constant)Member functions
operator bool
converts the object to bool, returns value
(public member function)operator()
(C++14)
returns value
(public member function)Member types
Type Definition value_typebooltypestd::integral_constant<bool,value>Possible implementation
template<classT>structis_pointer:std::false_type{};template<classT>structis_pointer<T*>:std::true_type{};template<classT>structis_pointer<T*const>:std::true_type{};template<classT>structis_pointer<T*volatile>:std::true_type{};template<classT>structis_pointer<T*constvolatile>:std::true_type{};Example
Run this code
#include<type_traits>intmain(){structA{intm;voidf(){}};intA::*mem_data_ptr=&A::m;// a pointer to member datavoid(A::*mem_fun_ptr)()=&A::f;// a pointer to member functionstatic_assert(""&&!std::is_pointer<A>::value&&!std::is_pointer_v<A>// same thing as above, but in C++17!&&!std::is_pointer<A>()// same as above, using inherited operator bool&&!std::is_pointer<A>{}// ditto&&!std::is_pointer<A>()()// same as above, using inherited operator()&&!std::is_pointer<A>{}()// ditto&&std::is_pointer_v<A*>&&std::is_pointer_v<Aconst*volatile>&&!std::is_pointer_v<A&>&&!std::is_pointer_v<decltype(mem_data_ptr)>&&!std::is_pointer_v<decltype(mem_fun_ptr)>&&std::is_pointer_v<void*>&&!std::is_pointer_v<int>&&std::is_pointer_v<int*>&&std::is_pointer_v<int**>&&!std::is_pointer_v<int[10]>&&!std::is_pointer_v<std::nullptr_t>&&std::is_pointer_v<void(*)()>);}See also
(C++11)
checks if a type is a pointer to a non-static member function or object
(class template)
(C++11)
checks if a type is a non-static member object pointer
(class template)
(C++11)
checks if a type is a non-static member function pointer
(class template)
(C++11)
checks if a type is an array type
(class template)
(C++11)
checks if a type is a scalar type
(class template)
(C++26)
checks if reflected type is a pointer type
(function)