| Defined in header
<type_traits> | ||
|---|---|---|
template<class B> struct negation; | (1) | (since C++17) |
Forms the logical negation of the type trait B.
The type std::negation<B> is a UnaryTypeTrait with a BaseCharacteristic of std::integral_constant<bool, !B::value>.
| B | - | any type such that B::value is convertible to bool |
template<class B> constexpr bool negation_v = negation<B>::value; | (since C++17) |
| value
[static]
| true if B has a member ::value that is false , false otherwise (public static member constant) |
| operator bool | converts the object to bool, returns value (public member function) |
| operator()
(C++14)
| returns value (public member function) |
| Type | Definition |
|---|---|
value_type | bool |
type | std::integral_constant<bool, value> |
template<class B>
struct negation : std::bool_constant<!B::value> { }; |
| (C++17)
| variadic logical AND metafunction (class template) |
| (C++17)
| variadic logical OR metafunction (class template) |
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