std::back_insert_iterator
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                    | Defined in header  <iterator> | ||
| template< class Container > class back_insert_iterator : public std::iterator< std::output_iterator_tag, | (until C++17) | |
| template< class Container > class back_insert_iterator; | (since C++17) | |
std::back_insert_iterator is an OutputIterator that appends to a container for which it was constructed. The container's push_back() member function is called whenever the iterator (whether dereferenced or not) is assigned to. Incrementing the std::back_insert_iterator is a no-op.
| Contents | 
[edit] Member types
| Member type | Definition | 
| container_type | Container | 
[edit] Member functions
| constructs a new back_insert_iterator(public member function) | |
| inserts an object into the associated container (public member function) | |
| no-op (public member function) | |
| no-op (public member function) | 
[edit] Member objects
| Member name | Definition | 
| container(protected) | a pointer of type Container* | 
[edit] Member types
| Member type | Definition | 
| value_type | void | 
| difference_type | void | 
| pointer | void | 
| reference | void | 
| iterator_category | std::output_iterator_tag | 
Note: before C++17, these member types are required to be obtained by inheriting from std::iterator<std::output_iterator_tag,void,void,void,void>.
[edit] Example
Run this code
#include <iostream> #include <iterator> #include <algorithm> #include <cstdlib> #include <vector> int main() { std::vector<int> v; std::generate_n(std::back_insert_iterator<std::vector<int>>(v), // can be simplified 10, [](){ return std::rand() % 10; }); // with std::back_inserter for (int n : v) std::cout << n << ' '; std::cout << '\n'; }
Output:
3 6 7 5 3 5 6 2 9 1
[edit] See also
| creates a std::back_insert_iterator of type inferred from the argument (function template) | |
| iterator adaptor for insertion at the front of a container (class template) | |
| iterator adaptor for insertion into a container (class template) | 


