std::is_integral
std::is_integral
Defined in header <type_traits>
|
||
---|---|---|
|
(since C++11) |
Checks whether T
is an integral type. Provides the member constant value
which is equal to true
, if T
is the type bool
, char
, char8_t
, char16_t
, char32_t
, wchar_t
, short
, int
, long
, long long
, or any implementation-defined extended integer types, including any signed, unsigned, and cv-qualified variants. Otherwise, value
is equal to false
.
Template parameters
T | - | a type to check |
Helper variable template
|
(since C++17) |
Inherited from std::integral_constant
Member constants
value [static] |
true if T is an integral 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 <iostream>
#include <type_traits>
class A {};
enum E : int {};
template <class T>
T f(T i)
{
static_assert(std::is_integral<T>::value, "Integral required.");
return i;
}
int main()
{
std::cout << std::boolalpha;
std::cout << std::is_integral<A>::value << '\n';
std::cout << std::is_integral<E>::value << '\n';
std::cout << std::is_integral<float>::value << '\n';
std::cout << std::is_integral<int>::value << '\n';
std::cout << std::is_integral<bool>::value << '\n';
std::cout << f(123) << '\n';
}
Output:
false
false
false
true
true
123
See also
[static] |
identifies integer types (public static member constant of std::numeric_limits) |
(C++11) |
checks if a type is a floating-point type (class template) |
(C++11) |
checks if a type is an arithmetic type (class template) |
(C++11) |
checks if a type is an enumeration type (class template) |
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