# std::is_integral

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< cpp‎ | types

Defined in header `<type_traits>` |  |
template< class T > struct is_integral; |  | (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, 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

template< class T > inline constexpr bool is_integral_v = is_integral<T>::value; |  | (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

Run this code

    #include <iostream>
    #include <type_traits>

    class A {};

    template <class T>
    T f(T i)
    {
        static_assert(std::is_integral<T>::value, "Integer required.");
        return i;
    }

    int main()
    {
        std::cout << std::boolalpha;
        std::cout << std::is_integral<A>::value << '\n';
        std::cout << std::is_integral<float>::value << '\n';
        std::cout << std::is_integral<int>::value << '\n';
        std::cout << f(123) << '\n';
    }

Output:

    false
    false
    true
    123

### See also

is_integer [static] | identifies integer types (public static member constant of `std::numeric_limits`)
is_floating_point (C++11) | checks if a type is floating-point type (class template)
is_arithmetic (C++11) | checks if a type is arithmetic type (class template)

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