[Boost-users] What's wrong with my code?

Subject: [Boost-users] What's wrong with my code?
From: Bill David (billdavidcn_at_[hidden])
Date: 2014-05-04 05:08:51

Hi all,

I meet a problem with some code with boost and want to ask for some help
here.

To the following code:

#include <list>

using namespace std;

#include "boost/function.hpp"

#include "boost/foreach.hpp"

#include "boost/bind.hpp"

using namespace boost;

void InsertItemHelper(list<int>& inContainer, list<int>::iterator&
ioPosition, const list<int>::value_type& inItem)

{

       ioPosition = inContainer.insert(ioPosition, inItem);

}

void WorkerFunction(const list<int>& inContainer, boost::function<void(int)>
const& inAddItemCallback)

{

       BOOST_FOREACH(auto item, inContainer)

       {

              inAddItemCallback(item);

       }

}

void Print(const list<int>& inContainer)

{

       BOOST_FOREACH(auto item, inContainer)

       {

              std::cout << item << endl;

       }

}

int main()

{

       list<int> sourceContainer;

       sourceContainer.push_back(1);

       sourceContainer.push_back(2);

       sourceContainer.push_back(3);

       list<int> targetContainer;

       list<int>::iterator pos = targetContainer.end();

       boost::function<void(int)> addItemCallbackFxn(boost::bind(&
InsertItemHelper, targetContainer, pos, _1));

       WorkerFunction(sourceContainer, addItemCallbackFxn);

       return 0;

}

When I run it on Windows with VS2012, I always get a “list insert iterator
outside range” error with:

inContainer.insert(ioPosition, inItem);

It seems targetContainer I passed to boost::bind is copied so that the
following debug error of STL is hit:

#if _HAS_ITERATOR_DEBUGGING
if (_Where._Mycont != this)
       _DEBUG_ERROR("list insert iterator outside range");
#endif /* _HAS_ITERATOR_DEBUGGING */

But I am passing targetContainer as a reference and after the error, I can
correctly get data in it.

Does anybody know what’s wrong behind?

Thanks,

BD