Question

there are 26 errors in this one sourceFile that I obtained from sourceForge. It is part of the Stanford CS106B library so should not have any errors.

A sample of errors:

• C2059: syntax error : ‘public C2990: ‘Iterator’ : non-class template
  has already been declared as a class template
• C2255: ‘friend’ : not allowed outside of a class definition
• C2146: syntax error : missing ‘;’ before identifier ‘foreachHook’
• C4430: missing type specifier – int assumed. Note: C++ does not support default-int
• C2065: ‘FE_State’: undeclared identifier

with this many errors, intuition is that there is probably one simple reason not 26 complicated reasons.

/*
 * File: private/bst.h
 * Last modified on Fri Jun  5 15:40:43 2009 by eroberts
 * -----------------------------------------------------
 * This file contains the private section of the bst.h interface.
 * This portion of the class definition is taken out of the bst.h
 * header so that the client need not have to see all of these
 * details.
 */

public:

/*
 * Class: BST<ElemType>::Iterator
 * ------------------------------
 * This interface defines a nested class within the BST template that
 * provides iterator access to the keys contained in the BST.
 */

    class Iterator {
    public:
        Iterator();
        bool hasNext();
        ElemType next();

    private:
        struct iteratorMarkerT {
            void *np;
            bool processed;
        };

        Iterator(BST *bstp);
        BST *bstp;
        Stack<iteratorMarkerT> stack;
        long timestamp;
        void advanceToNextNode();
        void findLeftmostChild();
        friend class BST;
    };
    friend class Iterator;
    ElemType foreachHook(FE_State & _fe);

/*
 * Deep copying support
 * --------------------
 * This copy constructor and operator= are defined to make a
 * deep copy, making it possible to pass/return trees by value
 * and assign from one tree to another. The entire contents of
 * the tree, including all elements, are copied. Each tree
 * element is copied from the original tree to the copy using
 * assignment (operator=). Making copies is generally avoided
 * because of the expense and thus, trees are typically passed
 * by reference, however, when a copy is needed, these operations
 * are supported.
 */
    const BST & operator=(const BST & rhs);
    BST(const BST & rhs);

private:

/* Type definition for node in the tree */
    struct nodeT {
        ElemType data;
        nodeT *left, *right;
        int bf;    /* AVL balance factor */
    };

/* Constant definitions */
    static const int BST_RIGHT_HEAVY = +1;
    static const int BST_IN_BALANCE = 0;
    static const int BST_LEFT_HEAVY = -1;

/* Instance variables */
    nodeT *root;
    int numNodes;
    long timestamp;
    int (*cmpFn)(ElemType, ElemType);

/* Private method prototypes */
    nodeT *recFindNode(nodeT *t, ElemType & key);
    bool recAddNode(nodeT * & t, ElemType & key, bool & createdNewNode);
    bool recRemoveNode(nodeT * & t, ElemType & key, bool & didRemove);
    bool removeTargetNode(nodeT * & t);
    void updateBF(nodeT * & t, int bfDelta);
    void recDeleteTree(nodeT *t);
    void recBSTAll(nodeT *t, void (*fn)(ElemType));
    void fixRightImbalance(nodeT * & t);
    void fixLeftImbalance(nodeT * & t);
    void rotateRight(nodeT * & t);
    void rotateLeft(nodeT * & t);
    void copyOtherEntries(const BST & other);

/* Template method prototypes */

    template <typename ClientDataType>
    void recBSTAll(nodeT *t, void (*fn)(ElemType, ClientDataType &),
                   ClientDataType & data);

Answer 1

This file does not form valid C++ on its own. If you read the comments, it is taken out of bst.h to form the private portion of the class, without clients (users of the library) needing to see the details. private/bst.h only makes sense when it’s #included into bst.h at the right place. The compiler will then parse it in the correct context.

Take a look at the file bst.h in the directory above this file (private/bst.h).