Reverse Iterator
The reverse iterator adaptor flips the direction of a base iterator's
motion. Invoking operator++() moves the base iterator backward and
invoking operator--() moves the base iterator forward.
template <class Iterator>
class reverse_iterator :
public iterator_adaptor< reverse_iterator<Iterator>, Iterator >
{
friend class iterator_core_access;
public:
reverse_iterator() {}
explicit reverse_iterator(Iterator x) ;
template<class OtherIterator>
reverse_iterator(
reverse_iterator<OtherIterator> const& r
, typename enable_if_convertible<OtherIterator, Iterator>::type* = 0 // exposition
);
private: // as-if specification
typename reverse_iterator::reference dereference() const { return *prior(this->base()); }
void increment() { --this->base_reference(); }
void decrement() { ++this->base_reference(); }
void advance(typename reverse_iterator::difference_type n)
{
this->base_reference() += -n;
}
template <class OtherIterator>
typename reverse_iterator::difference_type
distance_to(reverse_iterator<OtherIterator> const& y) const
{
return this->base_reference() - y.base();
}
};
The base Iterator must be a model of Bidirectional Traversal
Iterator. The resulting reverse_iterator will be a model of the
most refined standard traversal and access concepts that are modeled
by Iterator.
reverse_iterator();
| Requires: | Iterator must be Default Constructible. |
|---|
| Returns: | An instance of reverse_iterator with a
default constructed base object. |
|---|
explicit reverse_iterator(Iterator x);
| Returns: | An instance of reverse_iterator with a
base object copy constructed from x. |
|---|
template<class OtherIterator>
reverse_iterator(
reverse_iterator<OtherIterator> const& r
, typename enable_if_convertible<OtherIterator, Iterator>::type* = 0 // exposition
);
| Requires: | OtherIterator is implicitly convertible to Iterator. |
|---|
| Returns: | An instance of reverse_iterator that is a copy of r. |
|---|