std::negate<void>
Defined in header <functional> | ||
|---|---|---|
template<> class negate<void>; | (since C++14) |
std::negate<> is a specialization of std::negate with parameter and return type deduced.
Nested types
| Nested type | Definition |
|---|---|
is_transparent | unspecified |
Member functions
| operator() | returns its negated argument (public member function) |
std::negate<void>::operator()
template< class T >
constexpr auto operator()( T&& arg ) const
-> decltype(-std::forward<T>(arg));
|
Returns the result of negating arg.
Parameters
| arg | - | value to negate |
Return value
-std::forward<T>(arg).
Example
#include <complex>
#include <functional>
#include <iostream>
int main()
{
auto complex_negate = std::negate<void>{}; // “void” can be omitted
constexpr std::complex z(4, 2);
std::cout << z << '\n';
std::cout << -z << '\n';
std::cout << complex_negate(z) << '\n';
}Output:
(4,2) (-4,-2) (-4,-2)
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