Difference between revisions of "cpp/types/negation"
From cppreference.com
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===Possible implementation=== | ===Possible implementation=== | ||
Revision as of 22:20, 16 November 2016
| Defined in header <type_traits>
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||
| 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 Template:concept with a BaseCharacteristic of std::bool_constant<!bool(B::value)>.
Contents |
Template parameters
| B | - | any type such that B::value is convertible to bool |
Helper variable template
| template<class B> constexpr bool negation_v = negation<B>::value; |
(since C++17) | |
Inherited from std::integral_constant
Member constants
| value [static] |
true if B has a member ::value that is false when explicitly converted to bool , 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::bool_constant<!B::value> { }; |
Example
| This section is incomplete Reason: no example |
See also
| (C++17) |
variadic logical AND metafunction (class template) |
| (C++17) |
variadic logical OR metafunction (class template) |
