std::experimental::negation

From cppreference.com
Defined in header <experimental/type_traits>
template<class B>
struct negation;
(1) (library fundamentals TS v2)

Forms the logical negation of the type trait B.

The type negation<B> is a UnaryTypeTrait with a BaseCharacteristic of std::integral_constant<bool, !B::value>.

Template parameters

B - any type such that the expression !B::value is a valid converted constant expression of type bool

Helper variable template

template<class B>
constexpr bool negation_v = negation<B>::value;
(library fundamentals TS v2)

Inherited from std::integral_constant

Member constants

value
[static]
true if B has a member ::value such that !B::value is true , 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 B>
struct negation : std::integral_constant<bool, !B::value> { };

Example

See also

(C++17)
logical NOT metafunction
(class template)