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The Shared Container Iterator Range Generator

template <typename Container>
std::pair<
  shared_container_iterator<Container>,
  shared_container_iterator<Container>
>
make_shared_container_range(boost::shared_ptr<Container> const& container);
Class shared_container_iterator is meant primarily to return, using iterators, a range of values that we can guarantee will be alive as long as the iterators are. This is a convenience function to do just that. It is equivalent to
std::make_pair(make_shared_container_iterator(container->begin(),container),
               make_shared_container_iterator(container->end(),container));

Example

In the following example, a range of values is returned as a pair of shared_container_iterator objects.

shared_iterator_example3.cpp:

#include "shared_container_iterator.hpp"
#include "boost/shared_ptr.hpp"
#include "boost/tuple/tuple.hpp" // for boost::tie
#include <algorithm>              // for std::copy
#include <iostream>
#include <vector>


typedef boost::shared_container_iterator< std::vector<int> > iterator;

std::pair<iterator,iterator>
return_range() {
  boost::shared_ptr< std::vector<int> > range(new std::vector<int>());
  range->push_back(0);
  range->push_back(1);
  range->push_back(2);
  range->push_back(3);
  range->push_back(4);
  range->push_back(5);
  return boost::make_shared_container_range(range);
}


int main() {


  iterator i,end;

  boost::tie(i,end) = return_range();

  std::copy(i,end,std::ostream_iterator<int>(std::cout,","));
  std::cout.put('\n');

  return 0;
}

Though the range object only lives for the duration of the return_range call, the reference counted std::vector will live until i and end are both destroyed. The output from this example is the same as the previous two.


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