Doubly linked list compile error

*SOLVED*

Hi there,

I'm trying to construct my first Doubly Linked List, but am having trouble compiling.

This is my program:

main.cpp :

Code:

---

#include <iostream>
#include "node.h"
#include "doublylinkedlist.h"
using namespace std;

int main()
{
        system ("PAUSE");
        return 0;
}

---

node.h :

Code:

---

class Node
{
public:
        Node *pointertonextnode;//pointer to the next node of type node
        Node *pointertopreviousnode;//pointer to the previous node of type node

        int nodedatamember;//a node's data memeber
};

---

doublylinkedlist.h :

Code:

---

class doublylinkedlist
{
public:

        Node *pointertofrontoflist;//pointer to front of list 
        Node *pointertobackoflist;//pointer to back of list 

        //constructor to contruct a blank doubly linked list:
        doublylinkedlist()
        {
                pointertofrontoflist = NULL;
                pointertobackoflist = NULL;
        }

        void insertBeginningWhenListIsEmpty(doublylinkedlist List, Node newNode);
};

---

doublylinkedlist.cpp :

Code:

---

#include "doublylinkedlist.h"

void doublylinkedlist::insertBeginningWhenListIsEmpty(doublylinkedlist List, Node newNode)
{
        if(List.pointertofrontoflist == NULL)
        {
                List.pointertofrontoflist = newNode;
                List.pointertobackoflist = newNode;
                newNode.pointertonextnode = NULL;
                newNode.pointertopreviousnode = NULL;
        }
        else
        {
                cout << "Create a Insert before function";
                //insert before function
        }
}

---

In Visual Studio, the first compile error reports:

Quote:

---

error C2143: syntax error : missing ';' before '*'

---

Which is the line in bold within the doublylinkedlist.h file.

I can't see the error which would cause this, and so am stumped.

Could anyone point my error?

Many thanks for any help with this!


//-------------------------------------------------
(Full error list if that will help):

Quote:

---

error C2143: syntax error : missing ';' before '*'
error C4430: missing type specifier - int assumed. Note: C++ does not support default-int
error C4430: missing type specifier - int assumed. Note: C++ does not support default-int
error C2143: syntax error : missing ';' before '*'
error C4430: missing type specifier - int assumed. Note: C++ does not support default-int
error C4430: missing type specifier - int assumed. Note: C++ does not support default-int
error C2061: syntax error : identifier 'Node'
error C2065: 'pointertofrontoflist' : undeclared identifier
error C2065: 'NULL' : undeclared identifier
error C2065: 'pointertobackoflist' : undeclared identifier
error C2061: syntax error : identifier 'Node'
error C2039: 'pointertofrontoflist' : is not a member of 'doublylinkedlist'
see declaration of 'doublylinkedlist'
error C2039: 'pointertofrontoflist' : is not a member of 'doublylinkedlist'
see declaration of 'doublylinkedlist'
error C2065: 'newNode' : undeclared identifier
error C2039: 'pointertobackoflist' : is not a member of 'doublylinkedlist'
see declaration of 'doublylinkedlist'
error C2228: left of '.pointertonextnode' must have class/struct/union

---

doublylinkedlist can't see the definition of Node because it isn't including Node.h
Where are your include guards? (#pragma once of #ifndef xxx #define xx)

Thanks for helping iMalc, but I'm still having problems.

Did I make a mistake with what you suggested?

main.cpp:

Code:

---

#include <iostream>
#include "node.h"
#include "doublylinkedlist.h"
using namespace std;

int main()
{
        system ("PAUSE");
        return 0;
}

---

node.h:

Code:

---

#ifndef NODE.H
#define NODE.H

class Node
{
public:
        Node *pointertonextnode;//pointer to the next node of type node
        Node *pointertopreviousnode;//pointer to the previous node of type node

        int nodedatamember;//a node's data memeber
};

#endif

---

doublylinkedlist.h:

Code:

---

#ifndef DOUBLYLINKEDLIST.H
#define DOUBLYLINKEDLIST

#include "node.h"
class doublylinkedlist
{
public:

        Node *pointertofrontoflist;//pointer to front of list 
        Node *pointertobackoflist;//pointer to back of list 

        //constructor to contruct a blank doubly linked list:
        doublylinkedlist()
        {
                pointertofrontoflist = null;
                pointertobackoflist = null;
        }

        void insertBeginningWhenListIsEmpty(doublylinkedlist List, Node newNode);
};

#endif

---

doublylinkedlist.cpp:

Code:

---

#include "doublylinkedlist.h"
#include "node.h"
void doublylinkedlist::insertBeginningWhenListIsEmpty(doublylinkedlist List, Node newNode)
{
        if(List.pointertofrontoflist == NULL)
        {
                List.pointertofrontoflist = &newNode;
                List.pointertobackoflist = &newNode;
                newNode.pointertonextnode = NULL;
                newNode.pointertopreviousnode = NULL;
        }
        else
        {
                cout << "Create a Insert before function";
                //insert before fucntion
        }
}

---

Also made newNode a reference.

Visual Studio says:

Quote:

---

------ Build started: Project: List, Configuration: Debug Win32 ------
Compiling...
main.cpp
list\node.h(1) : warning C4067: unexpected tokens following preprocessor directive - expected a newline
list\node.h(2) : error C2008: '.' : unexpected in macro definition
list\doublylinkedlist.h(1) : warning C4067: unexpected tokens following preprocessor directive - expected a newline
list\node.h(1) : warning C4067: unexpected tokens following preprocessor directive - expected a newline
list\doublylinkedlist.h(15) : error C2065: 'null' : undeclared identifier doublylinkedlist.cpp
list\doublylinkedlist.h(1) : warning C4067: unexpected tokens following preprocessor directive - expected a newline
list\node.h(1) : warning C4067: unexpected tokens following preprocessor directive - expected a newline
list\my doubly linked list\node.h(2) : error C2008: '.' : unexpected in macro definition
list\doublylinkedlist.h(15) : error C2065: 'null' : undeclared identifier
list\node.h(1) : warning C4067: unexpected tokens following preprocessor directive - expected a newline
list\doublylinkedlist.cpp(5) : error C2065: 'NULL' : undeclared identifier
list\doublylinkedlist.cpp(14) : error C2065: 'cout' : undeclared identifier

---

Really appreciate any help with this :)

Thanks!


EDIT - I got it to compile now.

Thanks again iMalc :)

People most often use underscores in the define e.g.

Code:

---

#ifndef DOUBLYLINKEDLIST_H

---

but I guess you figured out that the dot was the problem and got something suitable.