W3cubDocs

/C++

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 true. For any other type, value is false.

Template parameters

T - 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 <iostream>
#include <type_traits>
 
class A {};
 
int main() 
{
    std::cout << std::boolalpha;
    std::cout << "A:           " <<  std::is_arithmetic<A>::value << '\n';
    std::cout << "bool:        " <<  std::is_arithmetic<bool>::value << '\n';
    std::cout << "int:         " <<  std::is_arithmetic<int>::value << '\n';
    std::cout << "int const:   " <<  std::is_arithmetic<int const>::value << '\n';
    std::cout << "int &:       " <<  std::is_arithmetic<int&>::value << '\n';
    std::cout << "int *:       " <<  std::is_arithmetic<int*>::value << '\n';
    std::cout << "float:       " <<  std::is_arithmetic<float>::value << '\n';
    std::cout << "float const: " <<  std::is_arithmetic<float const>::value << '\n';
    std::cout << "float &:     " <<  std::is_arithmetic<float&>::value << '\n';
    std::cout << "float *:     " <<  std::is_arithmetic<float*>::value << '\n';
    std::cout << "char:        " <<  std::is_arithmetic<char>::value << '\n';
    std::cout << "char const:  " <<  std::is_arithmetic<char const>::value << '\n';
    std::cout << "char &:      " <<  std::is_arithmetic<char&>::value << '\n';
    std::cout << "char *:      " <<  std::is_arithmetic<char*>::value << '\n';
}

Output:

A:           false
bool:        true
int:         true
int const:   true
int &:       false
int *:       false
float:       true
float const: true
float &:     false
float *:     false
char:        true
char const:  true
char &:      false
char *:      false

See also

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

© cppreference.com
Licensed under the Creative Commons Attribution-ShareAlike Unported License v3.0.
http://en.cppreference.com/w/cpp/types/is_arithmetic