std::logical_not

 

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Operator wrappers plus minus negate multiplies divides modulus bit_and bit_or bit_not (C++14)   bit_xor equal_to not_equal_to greater less greater_equal less_equal logical_and logical_or logical_not	Transparent operator wrappers plus<> (C++14) minus<> (C++14) negate<> (C++14) multiplies<> (C++14)   divides<> (C++14) modulus<> (C++14) bit_and<> (C++14) bit_or<> (C++14) bit_not<> (C++14) bit_xor<> (C++14) equal_to<> (C++14) not_equal_to<> (C++14) greater<> (C++14) less<> (C++14) greater_equal<> (C++14) less_equal<> (C++14) logical_and<> (C++14) logical_or<> (C++14) logical_not<> (C++14)
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Defined in header <functional>
template< class T > struct logical_not;

Function object for performing logical NOT (logical negation). Effectively calls operator! for type T.

Member types

Type	Definition
result_type	bool
argument_type	T

Member functions

operator()

returns the logical NOT of the argument (public member function)

std::logical_not::operator()

bool operator()( const T& arg ) const;

Returns the logical NOT of arg.

Parameters

arg

-

value to compute logical NOT of

Return value

The result of !arg.

Exceptions

(none)

Possible implementation

bool operator()(const T &arg) const { return !arg; }