NAME

std::back_insert_iterator - std::back_insert_iterator

Synopsis

Defined in header <iterator>
template< class Container >

class back_insert_iterator : public std::iterator< (until C++17)
std::output_iterator_tag,

void, void, void, void >
template< class Container > (since C++17)
class back_insert_iterator;

std::back_insert_iterator is a LegacyOutputIterator that appends elements 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.

Member types

Member type Definition
iterator_category std::output_iterator_tag
value_type void
difference_type void (until C++20)
std::ptrdiff_t (since C++20)
pointer void
reference void
container_type Container

Member types iterator_category, value_type, difference_type, pointer
and reference are required to be obtained by inheriting from (until C++17)
std::iterator<std::output_iterator_tag, void, void, void, void>.

Member functions

constructor constructs a new back_insert_iterator
(public member function)
operator= inserts an object into the associated container
(public member function)
operator* no-op
(public member function)
operator++ no-op
operator++(int) (public member function)

Member objects

Member name Definition
container (protected) a pointer of type Container*

Example

// Run this code

#include <iostream>
#include <iterator>
#include <algorithm>
#include <vector>

int main()
{
std::vector<int> v;
std::generate_n(
std::back_insert_iterator<std::vector<int>>(v), // C++17: std::back_insert_iterator(v)
10, [n=0]() mutable { return ++n; } // or use std::back_inserter helper
);

for (int n : v)
std::cout << n << ' ';
std::cout << '\n';
}

Output:

1 2 3 4 5 6 7 8 9 10