linker error

I am trying to fix a linker error the error basically states this when I type make:

g++ -Wall -ansi -c Proj5Aux.cpp
g++ -Wall -ansi -o Proj5 Proj5.cpp /afs/umbc.edu/users/d/a/dana3/pub/CMSC202/p4/KLSocket.o Proj5Aux.o Human.o Computer.o Player.o Boards.o Node.o Square.o Queue.o Exception.o
Proj5Aux.o: In function `Queue<Square>::Enqueue(Square const&)':
Proj5Aux.cpp:(.gnu.linkonce.t._ZN5QueueI6SquareE7E nqueueERKS0_+0x24): undefined reference to `Node<Square>::Node(Square const&)'
collect2: ld returned 1 exit status
make: *** [Proj5] Error 1

here is my makefile

Code:

---


COMPILER=g++
CFLAGS= -Wall -ansi
PROJECT1=Proj5
PROJECT2=Tourney
SOCKET=/afs/umbc.edu/users/d/a/dana3/pub/CMSC202/p4/KLSocket.o

$(PROJECT1) : Proj5.cpp $(SOCKET) Proj5Aux.o Boards.o Square.o Node.o Queue.o P\layer.o Human.o Computer.o Exception.o
        $(COMPILER) $(CFLAGS) -o $(PROJECT1) Proj5.cpp $(SOCKET) Proj5Aux.o Hum\an.o Computer.o Player.o Boards.o Node.o Square.o Queue.o Exception.o

Proj5Aux.o : Proj5Aux.cpp Proj5Aux.h
        $(COMPILER) $(CFLAGS) -c Proj5Aux.cpp

Human.o : Human.cpp Human.h
        $(COMPILER) $(CFLAGS) -c Human.cpp

Computer.o : Computer.cpp Computer.h
        $(COMPILER) $(CFLAGS) -c Computer.cpp

Player.o : Player.cpp Player.h
 $(COMPILER) $(CFLAGS) -c Player.cpp

Boards.o : Boards.cpp Boards.h
        $(COMPILER) $(CFLAGS) -c Boards.cpp

Node.o: Node.cpp Node.h
        $(COMPILER) $(CFLAGS) -c Node.cpp

Square.o: Square.cpp Square.h
        $(COMPILER) $(CFLAGS) -c Square.cpp


Queue.o: Queue.cpp Queue.h
        $(COMPILER) $(CFLAGS) -c Queue.cpp

Tourney.o: Tourney.cpp Tourney.h
        $(COMPILER) $(CFLAGS) -c Tourney.cpp

PlayerInfo.o: PlayerInfo.cpp PlayerInfo.h
        $(COMPILER) $(CFLAGS) -c PlayerInfo.cpp

Exception.o: Exception.cpp Exception.h
        $(COMPILER) $(CFLAGS) -c Exception.cpp

---

If u need to see files as well ask as u can see its about twenty of them

Quote:

---

Originally Posted by tasha302

If u need to see files as well ask as u can see its about twenty of them

---

Maybe just the one that defines Node<Square>::Node(Square const&) for now. Later folks may need to know the name of this header file and how it is #included in the file that contains Queue<Square>::Enqueue(Square const&).

Code:

---



#ifndef NODE_H
#define NODE_H

#include <iostream>
#include "Square.h"

using namespace std;
template <class T> class Node;
template <class T> class Queue;

template< class T >

class Node{

 public:

  //**********************************************************
  //Function    :Default constructor
  //PreCondition :None
  //PostCondition:data row = col =0, next = NULL
  //**********************************************************
  Node();


  //**********************************************************
  //Function    :Constructor
  //PreCondition :None
  //PostCondition:row and col set to value passed in, next = NULL
  //**********************************************************

  Node(const T&);

  //**********************************************************
  //Function    :retrieves next pointer
  //PreCondition :none
  //PostCondition:next pointer is returned
  //**********************************************************

  Node< T > *GetNext();

  //**********************************************************
  //Function    :sets next pointer
  //PreCondition :none
  //PostCondition:next = nodeptr
  //**********************************************************

  void SetNext(Node< T > *nodeptr);

  //**********************************************************
  //Function    :retrieves data in node
  //PreCondition :none
  //PostCondition:class containing data is returned
  //**********************************************************

  const T& GetData();

 private:

  T m_data;
  Node< T > *m_next;
  friend class Queue<T>;
};


#include "Node.cpp"

#endif

---

//implementation

Code:

---



#ifndef NODE_CPP
#define NODE_CPP

#include "Node.h"

using namespace std;


//**********************************************************
//Function    :Default constructor
//PreCondition :
//PostCondition:data holds two int = 0, next = NULL
//**********************************************************

template< class T >
Node<T>::Node() : m_data()
{
  m_next = NULL;
}

//**********************************************************
//Function    :constructor
//PreCondition :None
//PostCondition:row = row column =row next = NULL
//**********************************************************

template< class T >
Node<T>::Node(const T& Node_Data): m_data(Node_Data)
{
  m_next = NULL;
}

//**********************************************************
//Function    :get the next pointer
//PreCondition :none
//PostCondition:returns the next pointer
//**********************************************************

template< class T >
Node< T>* Node<T>::GetNext()
{
  return m_next;
}

//**********************************************************
//Function    : sets next pointer
//PreCondition : none
//PostCondition:next = nodeptr
//**********************************************************

template< class T >
void Node<T>::SetNext(Node<T> *nodeptr)
{
  m_next = nodeptr;
}

//**********************************************************
//Function    :retrieves data
//PreCondition :none
//PostCondition:data of the square class is returned
//**********************************************************

template< class T >
const T& Node<T>::GetData()
{
  return m_data;
}


#endif

---

//Queue Class

Code:

---



#ifndef QUEUE_CPP
#define QUEUE_CPP


#include "Queue.h"
#include <assert.h>
#include "Exception.h"

using namespace std;

//********************************************************
 //Function    : Constructor
 //PreCondition :
 //PostCondition:
 //********************************************************
 
template< class T >
Queue<T>::Queue()
{
  m_head = NULL;
  m_tail = NULL;
}

//********************************************************
//Function    : Destructor
//PreCondition :
//PostCondition: All things in queue would be destroyed
//********************************************************

template< class T >
Queue<T>::~Queue()
{
  DestroyQueue();

  m_head = NULL;
  m_tail = NULL;

}


//********************************************************
//Function    : copy constructor
//PreCondition : object is not empty
//PostCondition: object is copied into another object
//********************************************************

template< class T >
Queue<T>::Queue(const Queue<T>& A_Queue)
{
  m_head = m_tail = NULL;
  CopyQueue(A_Queue);
}



//********************************************************
//Function    : assignment operator
//PreCondition : not attempting a self copy
//PostCondition: object is copied into another object
//********************************************************

template< class T >
Queue<T>& Queue<T>::operator= (const Queue<T>& A_Queue)
{
  if(this != &A_Queue)
    CopyQueue(A_Queue);
  else
    throw ExceptClass("Attempting a self copy");
  return *this;

}
 
//********************************************************
//Function    : check if Queue is empty
//PreCondition : none
//PostCondition: true or false is returned
//********************************************************

template< class T >
bool Queue<T>::IsEmpty()const
{
  return (m_head == NULL);
}


//********************************************************
//Function    : places item into queue
//PreCondition : item being put in is not empty row and col
//              are between 0 and 9
//PostCondition: item is placed at the front of the queue
//********************************************************

template< class T >
void Queue<T>::Enqueue(const T& Queuedata)
{
 
 
    Node<T> *newNode;
    newNode = new Node<T>(Queuedata);

    if(newNode == NULL)
      throw ExceptClass("Attempting to Enqueue empty data");

    if(m_head == NULL)
      {
      m_head = newNode;
      m_tail = newNode;
   
      }
    else
      {
      m_tail->m_next = newNode;
      m_tail = m_tail->m_next;
   
      }
 

}



//********************************************************
//Function    : deletes item in queue(first item)
//PreCondition : queue is not empty
//PostCondition: first item is deleted from queue
//********************************************************

template< class T >
void Queue<T>::Dequeue()
{
  Node<T> *temp;

  if(!IsEmpty())
    {
      temp = m_head;
      m_head = m_head->m_next;
      delete temp;
      if(m_head == NULL)
        m_tail = NULL;
    }
  else
    throw ExceptClass("Queue is empty:: Nothing to remove");
}


//********************************************************
//Function    : retrieves item in the front of the queue
//PreCondition : queue is not empty
//PostCondition: item is returned to caller
//*******************************************************

template< class T >
const T& Queue<T>::Front()
{
  if( m_head == NULL)
    throw ExceptClass("Queue is empty: Nothing to retrieve");

  return m_head->m_data;
}



//********************************************************
//Function    : retrieves item from the back of the queue
//PreCondition : queue is not empty
//PostCondition: item is returned to caller
//********************************************************

template< class T >
const T& Queue<T>::Back()
{
  if (m_head == NULL)
    throw ExceptClass("Queue is empty: Nothing to retrieve");

  return m_tail->m_data;
}


//********************************************************
//Function    : Destroys every item in a queue
//PreCondition : queue is not empty
//PostCondition: queue is destroyed
//********************************************************

template< class T >
void Queue<T>::DestroyQueue()
{
  Node<T> *temp;

  while(!IsEmpty())
    {
      temp = m_head;
      m_head = m_head->m_next;
      delete temp;
    }
}



//********************************************************
//Function    : copies item from one queue to another queue
//PreCondition : queue is not empty
//PostCondition: object is copied to another object
//********************************************************

template< class T >
void Queue<T>::CopyQueue(const Queue<T>& A_Queue)
{
  if(m_head != NULL)
  m_head = m_tail = NULL;
  if(A_Queue.m_head == NULL)
    m_head = m_tail = NULL;
  else
    {
      Node<T> *temp;

      temp = A_Queue.m_head;
      m_head = new Node<T>;

      m_head->m_data = temp->m_data;
      m_head->m_next = NULL;
   
      m_tail = m_head;

      temp = temp->m_next;

      while(temp!= NULL)
        {
          Node<T> *newNode = new Node<T>;

          newNode->m_data = temp->m_data;
          newNode->m_next = NULL;
          m_tail->m_next = newNode;
          m_tail = newNode;
          temp = temp->m_next;
        }
    }
}



//*********************************************************************
//Function    : Outputs item in the queue to the screen
//Precondition : queue is not empty
//PostCondition: item is sent to the screen
//*********************************************************************
template<class T>
ostream& operator<< (ostream& out, const Queue<T>& A_Queue)
{

  Node<T> *temp = new Node<T>;

  temp = A_Queue.m_head;

  if(A_Queue.IsEmpty())
    throw ExceptClass("Queue is Empty: Nothing to output.");
  else
    {
      while(temp != NULL)
        {
          out<<"Items in queue are: "<<temp->GetData();
          temp = temp->GetNext();
        }
    }
  delete temp;
  return out;
}



#endif

---

You can't separate templated classes into header and source files like you do with normal classes. One solution is to place all of your cpp file code into the corresponding header file for the classes that are templated.

For more information see this FAQ and a few below it:

http://www.parashift.com/c++-faq-lit...html#faq-35.12