std::is_pod
Defined in header <type_traits> | ||
|---|---|---|
template< class T > struct is_pod; | (since C++11) (deprecated in C++20) |
std::is_pod is a UnaryTypeTrait.
If T is a POD type ("plain old data type"), provides the member constant value equal to true. For any other type, value is false.
If std::remove_all_extents_t<T> is an incomplete type and not (possibly cv-qualified) void, the behavior is undefined.
If the program adds specializations for std::is_pod or std::is_pod_v, the behavior is undefined.
Template parameters
| T | - | a type to check |
Helper variable template
template< class T > constexpr bool is_pod_v = is_pod<T>::value; | (since C++17) (deprecated in C++20) |
Inherited from std::integral_constant
Member constants
|
value
[static] |
true if T is a POD 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_type | bool |
type | std::integral_constant<bool,value> |
Example
#include <type_traits>
struct A { int m; };
static_assert(std::is_pod_v<A> == true);
class B: public A { int m; };
static_assert(std::is_pod_v<B> == false);
struct C { virtual void foo(); };
static_assert(std::is_pod_v<C> == false);
int main() {}
Defect reports
The following behavior-changing defect reports were applied retroactively to previously published C++ standards.
| DR | Applied to | Behavior as published | Correct behavior |
|---|---|---|---|
| LWG 2015 | C++11 |
T could be an array of incompleteclass type with unknown bound | the behavior is undefined in this case |
See also
|
(C++11) | checks if a type is a standard-layout type (class template) |
|
(C++11)(deprecated in C++26) | checks if a type is trivial (class template) |
|
(C++11) | checks if a type is a scalar type (class template) |
External links
Why is std::is_pod deprecated in C++20? — StackOverflow |
© cppreference.com
Licensed under the Creative Commons Attribution-ShareAlike Unported License v3.0.
https://en.cppreference.com/cpp/types/is_pod
