some comments

Llist.cpp

@@ -35,6 +35,8 @@ void Llist::display(ostream &out) const {
 
 void Llist::insertAfter(Node *p, ElementType d) {
   Node *n;
+
+  // p == NULL is interpreted as prepending
   if (p == NULL) {
     n = new Node(d, head);
     head = n;
@@ -65,6 +67,7 @@ ostream& operator<< (ostream &out, const Llist& L) {
 void Llist::printRev() const {
   printRev(head); 
 }
+
 void Llist::printRev(Node *p) const {
   if (p != NULL) {
     printRev(p->next);
@@ -74,22 +77,31 @@ void Llist::printRev(Node *p) const {
 
 void Llist::removeAfter(Node *cur) {
   Node *suc;
+
+  // cur == NULL is interpreted as removing the first
+  // node of the list
   if (cur == NULL and head != NULL) {
     suc = head->next;
     delete head;
     head = suc;
-
+    // in case the removed node was the only node
     if (suc == NULL) tail = NULL;
   }
   else if (cur->next != NULL) {
     suc = cur->next->next;
     delete cur->next;
     cur->next = suc;    
+    // if the removed node was the last, update the tail pointer
     if (suc == NULL) tail = cur;
   }
   length--;
 }
 
+// Assignment operator:
+// 1. empty the list of the invoking object
+// 2. traverse the list of the parameter appending each
+//    node data to the invoking object
+
 Llist& Llist::operator=(const Llist &L) {
   if (this != &L) {
     while(head != NULL) removeAfter(NULL);