std::not1 - cppreference.com (original) (raw)

| Defined in header | | | | -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | | ------------------------------------------------------ | | template< class Predicate > std::unary_negate<Predicate> not1( const Predicate& pred ); | | (until C++14) | | template< class Predicate > constexpr std::unary_negate<Predicate> not1( const Predicate& pred ); | | (since C++14) (deprecated in C++17) (removed in C++20) |

std::not1 is a helper function to create a function object that returns the complement of the unary predicate function passed. The function object created is of type std::unary_negate<Predicate>.

The unary predicate type must define a member type, argument_type, that is convertible to the predicate's parameter type. The unary function objects obtained from std::ref, std::cref, std::negate, std::logical_not, std::mem_fn, std::function, std::hash, or from another call to std::not1 have this type defined, as are function objects derived from the deprecated std::unary_function.

[edit] Parameters

[edit] Return value

std::not1 returns an object of type std::unary_negate<Predicate>, constructed with pred.

[edit] Exceptions

(none)

[edit] Example

[edit] See also