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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)

Checks whether T is an 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.

Contents

Template parameters

T - a type to check

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>
[edit template]

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

See also

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