std:: is_floating_point

From cppreference.com
C++
Metaprogramming library
Type traits
Type categories
(C++11)
(C++11)
(C++11)
(C++11)
is_floating_point
(C++11)
(C++11)
(C++11)
(C++11)
(C++11)
(C++11)
(C++11)
(C++11)
(C++11)
Type properties
(C++11)
(C++11)
(C++11)
(C++11)
(C++14)
(C++11)
(C++17)
(C++23)
(C++11) (deprecated in C++26)
(C++11)
(C++11)
(C++11) ( until C++20* )
(C++11) (deprecated in C++20)
(C++11)
(C++11)
(C++20)
(C++20)
(C++23)
(C++17)
Type trait constants
(C++11) (C++17) (C++11) (C++11)
Metafunctions
(C++17)
(C++17)
(C++17)
Supported operations
Relationships and property queries
Type modifications
Type transformations
(C++11) (deprecated in C++23)
(C++11) (deprecated in C++23)
(C++11)
(C++20)
(C++11)
(C++17)

(C++11)
(C++11)
(C++20)
(C++11)
(C++11) ( until C++20* ) (C++17)
(C++20)
Compile-time rational arithmetic
Compile-time integer sequences
(C++14)
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)
Retrieved from " https://en.cppreference.com/mwiki/index.php?title=cpp/types/is_floating_point&oldid=176473 "