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

NAME
     std::is_floating_point - std::is_floating_point

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

	std::is_floating_point is a UnaryTypeTrait.

	Checks	whether T is a floating-point type. Provides the member constant
     value which
	is equal to true, if T is the type float, double, long double
	, or any extended floating-point types (std::float16_t, std::float32_t,
	std::float64_t, std::float128_t, or std::bfloat16_t)
	(since C++23), including any cv-qualified variants. Otherwise, value  is
     equal to
	false.

	If the program adds specializations for std::is_floating_point or
	std::is_floating_point_v, the behavior is undefined.

Template parameters
	T - a type to check

	Helper variable template

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

     Inherited from std::integral_constant

Member constants
	value	 true if T is a  floating-point  type  (possibly  cv-qualified),
     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>

Possible implementation
	template<class T>
	struct is_floating_point
	     : std::integral_constant<
		 bool,
		 // Note: standard floating-point types
		 std::is_same<float, typename std::remove_cv<T>::type>::value
		 ||	    std::is_same<double,	typename	std::re-
     move_cv<T>::type>::value
		 ||	std::is_same<long     double,	  typename	std::re-
     move_cv<T>::type>::value
		 // Note: extended floating-point types (C++23, if supported)
		 ||	 std::is_same<std::float16_t,	   typename	std::re-
     move_cv<T>::type>::value
		 ||	std::is_same<std::float32_t,	  typename	std::re-
     move_cv<T>::type>::value
		 ||	 std::is_same<std::float64_t,	   typename	std::re-
     move_cv<T>::type>::value
		 ||	std::is_same<std::float128_t,	  typename	std::re-
     move_cv<T>::type>::value
		 ||	 std::is_same<std::bfloat16_t,	   typename	std::re-
     move_cv<T>::type>::value
	     > {};

Example
     // Run this code

      #include <iostream>
      #include <type_traits>

      class A {};

      int main()
      {
	  std::cout << std::boolalpha;
	  std::cout << "      A: " << std::is_floating_point<A>::value << '\n';
	  std::cout << "  float: "  <<	std::is_floating_point<float>::value  <<
     '\n';
	  std::cout  <<  " float&: " << std::is_floating_point<float&>::value <<
     '\n';
	  std::cout << " double: " <<  std::is_floating_point<double>::value  <<
     '\n';
	  std::cout  << "double&: " << std::is_floating_point<double&>::value <<
     '\n';
	  std::cout << "     int:  "  <<  std::is_floating_point<int>::value  <<
     '\n';
      }

Output:
	    A: false
	float: true
       float&: false
       double: true
      double&: false
	  int: false

See also
	is_iec559      identifies the IEC 559/IEEE 754 floating-point types
	[static]       (public static member constant of std::numeric_limits<T>)
	is_integral    checks if a type is an integral type
	(C++11)        (class template)
	is_arithmetic  checks if a type is an arithmetic type
	(C++11)        (class template)
	floating_point specifies that a type is a floating-point type
	(C++20)        (concept)

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