std::is_floating_point - cppreference.com

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# std::is_floating_point

From cppreference.com
< cpp‎ | types

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.

### [edit] Template parameters

T | - | a type to check

### [edit] Helper variable template

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

[edit]

## 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] 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
                               > {};

### [edit] Example

Run this code

    #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

### [edit] See also

is_iec559 [static] | identifies the IEC 559/IEEE 754 floating-point types (public static member constant of `std::numeric_limits`) [edit]
is_integral (C++11) | checks if a type is integral type (class template) [edit]
is_arithmetic (C++11) | checks if a type is arithmetic type (class template) [edit]
std::experimental::is_floating_point_v (library fundamentals TS) | variable template alias of `std::is_floating_point::value` (variable template) [edit]

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