templates - Printing Objects via "<<" in a Linked-List in C++ -

for assignment (and myself) need able print singlely linked list of "stock" objects.

each stock following private data members: 1 int 1 string

this print function in linked list class had use/develop. not allowed use stl::list().

//list.h template<class nodetype> void list< nodetype>::print() const { if(isempty() ){     cout<<"the list empty\n\n";     return; }  listnode< nodetype> *currentptr=firstptr;  cout<<"the list is: ";  while (currentptr!=0){     //cout << currentptr->data << ' ';     currentptr = currentptr->nextptr; }  cout<< "\n\n"; } 

now nodes in list, listnode.h:

//listnode.h //listnode template definition #ifndef listnode_h #define listnode_h  template< class nodetype > class list;  template < class nodetype> class listnode { friend class list < nodetype>;  public:     listnode (const nodetype &); //constructor     nodetype getdata() const;  private:    nodetype data;    listnode< nodetype> *nextptr;  };   template<class nodetype>  listnode< nodetype >::listnode(const nodetype &info): data (info), nextptr(0)  {   }  template<class nodetype>  nodetype listnode<nodetype>::getdata() const{     return data;  }  #endif 

now stock class:

class stock{ public:     stock(); //default constructor     stock(string, int); //overloaded constructor     ~stock(); //deconstructor     void setsymbol(string); //sets stock symbol     void setshares(int);     string getsymbol();     int getshares(); private:     string symbol;     int shares; }; stock::stock(){ symbol=" "; shares=0; } stock::stock(string s, int num){     cout<<"creating stock supplied values! \n\n"<<endl;     symbol=s;     shares=num;     price=p; } 

simple int main() testing:

int main(){  list < stock > portfolio_list;  stock google("goog", 500); stock vmware("vmw", 90); stock apple("apl", 350);  portfolio_list.insertatfront(google); portfolio_list.insertatfront(vmware); portfolio_list.insertatfront(apple);  portfolio_list.print();  return 0;  } 

so obviously, operator errors "<<" in list.h, because can't output contents of stock class. end goal loop through every element in linked list , print string symbol , int. i'm assuming need use sort of operator overloading? or way off base? if do, should implemented in stock class? in advance.

if understood code, you'll have overload << operator both listnode , list classes.

//representation of listnode template <class t> ostream& operator << (ostream& ostr, listnode<t>& ls) {     return ostr << "foo"; //replace "foo" proper representation }  //representation of list template <class t> ostream& operator << (ostream& ostr, list<t>& ls) {     ostr << "[ ";     for(listnode<t> *i = ls.firstptr; != null; = i->nextptr)         ostr << *i << " ";     return ostr << "]"; } 

would print [ foo foo foo ] 3 element list.

btw, should mark functions friend if need access private members.