So given this header. template < QSTYPE type, typename T, template class CONT > CONT<T> quicksort(CONT<T>); // inside the main file. // I decided a function that takes vector of integer and returns a vector of integer. typedef boost::function sortfunc; // create a function list to hold the sorting function. // bunch of number include. #include std::vector<sortfunc> function_list; using boost::assign::operator+=; std::vector<sortfunc> function_list; // quicksort random function_list += (&algocpw::quicksort), // quicksort median (&algocpw::quicksort), // quicksort mediantriple (&algocpw::quicksort), // merge sort (&algocpw::mergesort), // heap sort (&algocpw::heapsort), // selection sort (&algocpw::selection_sort), // standard sort (&algocpw::standard_sort); I get the following errors. ./cs512/c++/sortingMain.cpp(63) : error C2896: 'boost::assign::list_inserter>,V> boost::assign::operator +=(std::vector<_Ty,_Alloc> &,V2)' : cannot use function template 'CONT<T> algocpw::mergesort(CONT<T>)' as a function argument c:\cpw\msvc\cs512\c++\def\../sortingAlgo.hpp(32) : see declaration of 'algocpw::mergesort' ./cs512/c++/sortingMain.cpp(63) : error C2784: 'boost::assign::list_inserter>,V> boost::assign::operator +=(std::deque &,V2)' : could not deduce template argument for 'std::deque &' from 'std::vector<_Ty>' with [ _Ty=sortfunc ] Where did "deque" come from.. i never included deque.