Library: Iterators
insert_iterator iterator
An iterator adaptor that allows an iterator to insert into a container rather than overwrite elements in the container
#include <iterator>
namespace std {
template <class Container>
class insert_iterator;
template <class Container>
class back_insert_iterator;
template <class Container>
class front_insert_iterator;
}
Insert iterators are iterator adaptors that let an iterator insert new elements into a collection rather than overwrite existing elements when copying to a container. There are several types of insert iterator classes.
The class back_insert_iterator is used to insert items at the end of a collection. The function back_inserter() can be used with an iterator inline, to create an instance of a back_insert_iterator for a particular collection type.
The class front_insert_iterator is used to insert items at the start of a collection. The function front_inserter() creates an instance of a front_insert_iterator for a particular collection type.
An insert_iterator inserts new items into a collection at a location defined by an iterator supplied to the constructor. Like the other insert iterators, insert_iterator has a helper function called inserter(), which takes a collection and an iterator into that collection, and creates an instance of the insert_iterator.
namespace std{
template <class Container>
class insert_iterator : public
iterator<output_iterator_tag,void,void,void,void>; {
public:
typedef Container container_type;
insert_iterator(Container&, typename
Container::iterator);
insert_iterator<Container>&
operator=(const typename Container::value_type&);
insert_iterator<Container>& operator*();
insert_iterator<Container>& operator++();
insert_iterator<Container>& operator++(int);
};
template <class Container>
class back_insert_iterator : public
iterator<output_iterator_tag,void,void,void,void> ; {
public:
typedef Container container_type;
explicit back_insert_iterator(Container&);
back_insert_iterator<Container>&
operator=(const typename Container::value_type&);
back_insert_iterator<Container>& operator*();
back_insert_iterator<Container>& operator++();
back_insert_iterator<Container> operator++(int);
};
template <class Container>
class front_insert_iterator : public
iterator<output_iterator_tag,void,void,void,void>;
{
public:
typedef Container container_type;
explicit front_insert_iterator(Container&);
front_insert_iterator<Container>&
operator=(const typename Container::value_type&);
front_insert_iterator<Container>& operator*();
front_insert_iterator<Container>& operator++();
front_insert_iterator<Container> operator++(int);
};
template <class Container, class Iterator>
insert_iterator<Container> inserter(Container&, Iterator);
template <class Container>
back_insert_iterator<Container> back_inserter(Container&);
template <class Container>
front_insert_iterator<Container>
front_inserter(Container&);
}
back_insert_iterator, front_insert_iterator, insert_iterator
ISO/IEC 14882:1998 -- International Standard for Information Systems -- Programming Language C++, Section 24.4.2