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std::is_arithmetic(3)	       C++ Standard Libary	   std::is_arithmetic(3)

NAME
     std::is_arithmetic - std::is_arithmetic

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

	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
	T - a type to check

	Helper variable template

	template< class T >						  (since
     C++17)
	inline constexpr bool is_arithmetic_v = is_arithmetic<T>::value;

     Inherited from std::integral_constant

Member constants
	value	 true if T is an arithmetic type, false otherwise
	[static] (public static member constant)

Member functions
	operator bool converts the object to bool, returns value
		      (public member function)
	operator()    returns value
	(C++14)       (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 opera-
     tors (+, -, *,
	/) are defined (possibly in combination with the usual	arithmetic  con-
     versions).

	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_float-
     ing_point<T>::value> {};

Example
     // Run this code

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

http://cppreference.com 	   2024.06.10		   std::is_arithmetic(3)
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