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 base characteristic of std::integral_constant<bool, !bool(B::value)>.

Template parameters

B - any type such that the expression bool(B::value) is a valid constant expression

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 !bool(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, !bool(B::value)> {};

Example

See also

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