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std::is_arithmetic - cppreference.com

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template< class T > struct is_arithmetic;

 (since C++11)

std::is_arithmetic is a UnaryTypeTrait.

If T is an arithmetic type (that is, an integral type or a floating-point type) or a cv-qualified version thereof, provides the member constant value equal to true. For any other type, value is false.

If the program adds specializations for std::is_arithmetic or std::is_arithmetic_v(since C++17), the behavior is undefined.

Template parameters

Helper variable template

template< class T > constexpr bool is_arithmetic_v = is_arithmetic<T>::value;

 (since C++17)

Inherited from std::integral_constant

Member constants

true if T is an arithmetic type, false otherwise
(public static member constant)

Member functions

converts the object to bool, returns value
(public member function)
returns value
(public member function)

Member types

Type Definition
value_type bool
type std::integral_constant<bool, value>

Notes

Arithmetic types are the built-in types for which the arithmetic operators (+, -, *, /) are defined (possibly in combination with the usual arithmetic conversions).

Specializations of std::numeric_limits are provided for all arithmetic types.

Possible implementation

template<class T>
struct is_arithmetic : std::integral_constant<bool,
                                              std::is_integral<T>::value ||
                                              std::is_floating_point<T>::value> {};

Example

#include <atomic>
#include <cstddef>
#include <type_traits>

class A {};

enum class B : int { e };

static_assert(
    std::is_arithmetic_v<bool>            == true  and
    std::is_arithmetic_v<char>            == true  and
    std::is_arithmetic_v<char const>      == true  and
    std::is_arithmetic_v<int>             == true  and
    std::is_arithmetic_v<int const>       == true  and
    std::is_arithmetic_v<float>           == true  and
    std::is_arithmetic_v<float const>     == true  and
    std::is_arithmetic_v<std::size_t>     == true  and

    std::is_arithmetic_v<char&>           == false and
    std::is_arithmetic_v<char*>           == false and
    std::is_arithmetic_v<int&>            == false and
    std::is_arithmetic_v<int*>            == false and
    std::is_arithmetic_v<float&>          == false and
    std::is_arithmetic_v<float*>          == false and
    std::is_arithmetic_v<A>               == false and
    std::is_arithmetic_v<B>               == false and
    std::is_arithmetic_v<decltype(B::e)>  == false and
    std::is_arithmetic_v<std::byte>       == false and
    std::is_arithmetic_v<std::atomic_int> == false
);

int main() {}

See also