std::is_pod
From cppreference.com
Defined in header <type_traits>
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template< class T > struct is_pod; |
(since C++11) (deprecated in C++20) |
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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.
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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) |
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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
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bool |
type
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std::integral_constant<bool, value> |
Example
Run this code
#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 |
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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) |
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
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