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std::is_floating_point

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

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, including any cv-qualified variants. Otherwise, value is equal to false.

Template parameters

a type to check

Helper variable template

template< class T >
inline 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 , 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,
         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
     > {};

Example

#include <iostream>
#include <type_traits>
 
class A {};
 
int main() 
{
    std::cout << std::boolalpha;
    std::cout << std::is_floating_point<A>::value << '\n';
    std::cout << std::is_floating_point<float>::value << '\n';
    std::cout << std::is_floating_point<int>::value << '\n';
}

Output:

false
true
false

is_iec559 [static]	identifies the IEC 559/IEEE 754 floating-point types (public static member constant of `std::numeric_limits`)
is_integral (C++11)	checks if a type is integral type (class template)
is_arithmetic (C++11)	checks if a type is arithmetic type (class template)