std:: logical_not<void>

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Utilities library
General utilities
Relational operators (deprecated in C++20)
Function objects
Function invocation
(C++17) (C++23)
Identity function object
(C++20)
Old binders and adaptors
( until C++17* )
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( until C++17* )
( until C++17* ) ( until C++17* ) ( until C++17* ) ( until C++17* )
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Defined in header <functional>
template <>
class logical_not < void > ;
(since C++14)

std:: logical_not < void > is a specialization of std::logical_not with parameter and return type deduced.

Nested types

Nested type Definition
is_transparent unspecified

Member functions

operator()
applies operator! to its argument
(public member function)

std::logical_not<void>:: operator()

template < class T >

constexpr auto operator ( ) ( T && arg ) const

- > decltype ( ! std:: forward < T > ( arg ) ) ;

Returns the result of ! std:: forward < T > ( arg ) .

Parameters

arg - value to apply logical NOT to

Return value

! std:: forward < T > ( arg ) .

Example