std::is_trivial
From cppreference.com
| Defined in header <type_traits>
|
||
| template< class T > struct is_trivial; |
(since C++11) | |
If T is TrivialType (that is, a scalar type, a trivially copyable class with a trivial default constructor, or array of such type/class, possibly cv-qualified), provides the member constant value equal true. For any other type, value is false.
The behavior is undefined if std::remove_all_extents_t<T> is an incomplete type and not (possibly cv-qualified) void.
Contents |
[edit] Template parameters
| T | - | a type to check |
[edit] Helper variable template
| template< class T > inline constexpr bool is_trivial_v = is_trivial<T>::value; |
(since C++17) | |
Inherited from std::integral_constant
Member constants
| value [static] |
true if T is a trivial 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> |
[edit] Possible implementation
template< class T > struct is_trivial : std::integral_constant< bool, std::is_trivially_copyable<T>::value && std::is_trivially_default_constructible<T>::value > {}; |
[edit] Example
Run this code
#include <iostream> #include <type_traits> struct A { int m; }; struct B { B() {} }; int main() { std::cout << std::boolalpha; std::cout << std::is_trivial<A>::value << '\n'; std::cout << std::is_trivial<B>::value << '\n'; }
Output:
true false
[edit] See also
| (C++11) |
checks if a type is trivially copyable (class template) |
