std::is_floating_point

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

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

Inherited from std::integral_constant

Member constants

value
[static]
 true if T is a floating-point type (possibly cv-qualified), 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>

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::remove_cv<T>::type>::value
         || std::is_same<long double, typename std::remove_cv<T>::type>::value
         // Note: extended floating-point types (C++23, if supported)
         || std::is_same<std::float16_t, typename std::remove_cv<T>::type>::value
         || std::is_same<std::float32_t, typename std::remove_cv<T>::type>::value
         || std::is_same<std::float64_t, typename std::remove_cv<T>::type>::value
         || std::is_same<std::float128_t, typename std::remove_cv<T>::type>::value
         || std::is_same<std::bfloat16_t, typename std::remove_cv<T>::type>::value
     > {};

Example

Run this code
#include <type_traits>
 
class A {};
static_assert(!std::is_floating_point_v<A>);
 
static_assert(std::is_floating_point_v<float>);
static_assert(!std::is_floating_point_v<float&>);
static_assert(std::is_floating_point_v<double>);
static_assert(!std::is_floating_point_v<double&>);
static_assert(!std::is_floating_point_v<int>);
 
int main() {}

See also

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