negators(3)
NAME
Negators
Detailed Description
The functions not1 and not2 each take a predicate functor and return an instance of unary_negate or binary_negate, respectively. These classes are functors whose operator() performs the stored predicate function and then returns the negation of the result.
- For example, given a vector of integers and a trivial predicate,
- struct IntGreaterThanThree
: public std::unary_function<int, bool>
- {
bool operator() (int x) { return x > 3; }
- };
- std::find_if (v.begin(), v.end(), not1(IntGreaterThanThree()));
- The call to find_if will locate the first index (i) of v for which
- '!(v[i] > 3)' is true.
- The not1/unary_negate combination works on predicates taking a single
argument. The not2/binary_negate combination works on predicates which take two arguments. - Classes
- class std::binary_negate< _Predicate >
One of the negation functors.
- class std::unary_negate< _Predicate >
One of the negation functors.
- Functions
- template<typename _Predicate> unary_negate< _Predicate > std::not1
(const _Predicate &__pred)
- template<typename _Predicate> binary_negate< _Predicate > std::not2
(const _Predicate &__pred)
Function Documentation
- template<typename _Predicate> unary_negate<_Predicate> std::not1 (const
- _Predicate & __pred) [inline] One of the negation functors.
- Definition at line 360 of file stl_function.h.
- template<typename _Predicate> binary_negate<_Predicate> std::not2 (const
- _Predicate & __pred) [inline] One of the negation functors.
- Definition at line 385 of file stl_function.h.