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std::is_arithmetic

Defined in header `<type_traits>`
template< class T > struct is_arithmetic;		(since C++11)

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.

The behavior of a program that adds specializations for is_arithmetic or is_arithmetic_v (since C++17) is undefined.

Template parameters

a type to check

Helper variable template

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

(since C++17)

Inherited from std::integral_constant

Member constants

value

[static]

true if T is an arithmetic 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>

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 <type_traits>
 
class A {};
 
static_assert(
    std::is_arithmetic_v<A>           == false  and
    std::is_arithmetic_v<bool>        == true   and
    std::is_arithmetic_v<int>         == true   and
    std::is_arithmetic_v<int const>   == true   and
    std::is_arithmetic_v<int&>        == false  and
    std::is_arithmetic_v<int*>        == false  and
    std::is_arithmetic_v<float>       == true   and
    std::is_arithmetic_v<float const> == true   and
    std::is_arithmetic_v<float&>      == false  and
    std::is_arithmetic_v<float*>      == false  and
    std::is_arithmetic_v<char>        == true   and
    std::is_arithmetic_v<char const>  == true   and
    std::is_arithmetic_v<char&>       == false  and
    std::is_arithmetic_v<char*>       == false
);
 
int main() {}

is_integral (C++11)	checks if a type is an integral type (class template)
is_floating_point (C++11)	checks if a type is a floating-point type (class template)