std::front_insert_iterator
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                    |   Defined in header <iterator>
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|   template< class Container > class front_insert_iterator : public std::iterator< std::output_iterator_tag,  | 
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std::front_insert_iterator is an output iterator that prepends elements to a container for which it was constructed, using the container's push_front() member function whenever the iterator (whether dereferenced or not) is assigned to. Incrementing the std::front_insert_iterator is a no-op.
Contents | 
[edit] Member types
| Member type | Definition | 
| container_type | Container | 
[edit] Member objects
| Member name | Definition | 
| container (protected) | a pointer of type Container* | 
[edit] Member functions
|   constructs a new front_insert_iterator  (public member function)  | |
|    prepends an object to the associated container   (public member function)  | |
|    no-op   (public member function)  | |
|    no-op   (public member function)  | |
Inherited from std::iterator
Member types
| Member type | Definition | 
| value_type | void | 
| difference_type | void | 
| pointer | void | 
| reference | void | 
| iterator_category | std::output_iterator_tag | 
[edit] Example
#include <vector> #include <deque> #include <iostream> #include <iterator> #include <algorithm> int main() { std::vector<int> v{1,2,3,4,5}; std::deque<int> d; std::copy(v.begin(), v.end(), std::front_insert_iterator<std::deque<int>>(d)); // or std::front_inserter(d) for(int n : d) std::cout << n << ' '; std::cout << '\n'; }
Output:
5 4 3 2 1
[edit] See also
|    creates a std::front_insert_iterator of type inferred from the argument  (function template)  | |
|    iterator adaptor for insertion at the end of a container   (class template)  | |
|    iterator adaptor for insertion into a container  (class template)  | |