std::is_scalar
From cppreference.com
Defined in header
<type_traits>
|
||
template< class T >
struct is_scalar; |
(since C++11) | |
If T
is a scalar type (that is, arithmetic type, enumeration type, pointer, pointer to member, or std::nullptr_t, including any cv-qualified variants), provides the member constant value
equal true. For any other type, value
is false.
Contents |
Inherited from std::integral_constant
Member constants
value
[static]
|
true if T is a scalar 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] Notes
Each individual memory location in the C++ memory model, including the hidden memory locations used by language features (e.g virtual table pointer), has scalar type (or is a sequence of adjacent bit-fields of non-zero length). Sequencing of side-effects in expression evaluation, interthread synchronization, and dependency ordering are all defined in terms of individual scalar objects.
[edit] Possible implementation
template< class T > struct is_scalar : std::integral_constant<bool, std::is_arithmetic<T>::value || std::is_enum<T>::value || std::is_pointer<T>::value || std::is_member_pointer<T>::value || std::is_same<std::nullptr_t, typename std::remove_cv<T>::type>::value> {}; |
[edit] Example
Run this code
Output:
T is scalar T is not a scalar
[edit] See also
(C++11)
|
checks if a type is arithmetic type (class template) |
(C++11)
|
checks if a type is an enumeration type (class template) |
(C++11)
|
checks if a type is a pointer type (class template) |
(C++11)
|
checks if a type is a pointer to a non-static member function or object (class template) |
(library fundamentals TS)
|
variable template alias of std::is_scalar::value (variable template) |