std::negate<void>
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negate<>
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Defined in header
<functional>
template<>
class negate<void>;
(since C++14)
class negate<void>;
std::negate <> is a specialization of std::negate with parameter and return type deduced.
Contents
[edit] Member types
Type
Definition
is_transparent
unspecified
[edit] Member functions
operator()
(public member function)
std::negate<void>::operator()
template< class T >
constexpr auto operator()( T&& arg ) const
Returns the result of negating arg.
Parameters
arg
-
value to negate
Return value
-std::forward <T>(arg).
[edit] Example
Run this code
#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)