--- stack/stack.c	2002/01/09 05:01:24	1.13
+++ stack/stack.c	2002/01/31 19:51:12	1.14
@@ -25,6 +25,8 @@
 typedef stackitem* hashtbl[HASHTBLSIZE];
 typedef void (*funcp)(stackitem**);
 
+
+/* Initiates a newly created hash table. */
 void init_hashtbl(hashtbl out_hash)
 {
   long i;
@@ -33,6 +35,7 @@
     out_hash[i]= NULL;
 }
 
+/* Returns a pointer to an element in the hash table. */
 stackitem** hash(hashtbl in_hashtbl, const char* in_string)
 {
   long i= 0;
@@ -61,7 +64,7 @@
   }
 }
 
-
+/* Generic push function. */
 int push(stackitem** stack_head, stackitem* in_item)
 {
   in_item->next= *stack_head;
@@ -69,6 +72,7 @@
   return 1;
 }
 
+/* Push a value on the stack. */
 int push_val(stackitem** stack_head, int in_val) 
 {
   stackitem* new_item= malloc(sizeof(stackitem));
@@ -79,6 +83,7 @@
   return 1;
 }
 
+/* Copy a string onto the stack. */
 int push_cstring(stackitem** stack_head, const char* in_string)
 {
   stackitem* new_item= malloc(sizeof(stackitem));
@@ -90,6 +95,7 @@
   return 1;
 }
 
+/* Create a new hash entry. */
 int mk_hashentry(hashtbl in_hashtbl, stackitem* in_item, const char* id)
 {
   in_item->id= malloc(strlen(id)+1);
@@ -100,6 +106,7 @@
   return 1;
 }
 
+/* Define a function a new function in the hash table. */
 void def_func(hashtbl in_hashtbl, funcp in_func, const char* id)
 {
   stackitem* temp= malloc(sizeof(stackitem));
@@ -110,6 +117,7 @@
   mk_hashentry(in_hashtbl, temp, id);
 }
 
+/* Define a new symbol in the hash table. */
 void def_sym(hashtbl in_hashtbl, const char* id)
 {
   stackitem* temp= malloc(sizeof(stackitem));
@@ -119,6 +127,7 @@
   mk_hashentry(in_hashtbl, temp, id);
 }
 
+/* Push a reference to an entry in the hash table onto the stack. */
 int push_ref(stackitem** stack_head, hashtbl in_hash, const char* in_string)
 {
   static void* handle= NULL;
@@ -146,6 +155,7 @@
   return 1;
 }
 
+/* Discard the top element of the stack. */
 extern void toss(stackitem** stack_head)
 {
   stackitem* temp= *stack_head;
@@ -160,11 +170,13 @@
   free(temp);
 }
 
+/* Print newline. */
 extern void nl()
 {
   printf("\n");
 }
 
+/* Prints the top element of the stack. */
 void print_(stackitem** stack_head)
 {
   if((*stack_head)==NULL)
@@ -187,13 +199,14 @@
   }
 }
 
+/* Prints the top element of the stack and then discards it. */
 extern void print(stackitem** stack_head)
 {
   print_(stack_head);
   toss(stack_head);
 }
 
-/* print_stack(stack); */
+/* Only to be called by function printstack. */
 void print_st(stackitem* stack_head, long counter)
 { 
   if(stack_head->next != NULL)
@@ -204,6 +217,7 @@
   nl();
 }
 
+/* Prints the stack. */
 extern void printstack(stackitem** stack_head)
 {
   if(*stack_head != NULL) {
@@ -212,7 +226,9 @@
   }
 }
 
-
+/* If the top element is a reference, determine if it's a reference to a
+   function, and if it is execute and pop the reference and execute the
+   function. */
 extern void eval(stackitem** stack_head)
 {
   funcp in_func;
@@ -228,6 +244,7 @@
   }
 }
 
+/* Parse input. */
 int stack_read(stackitem** stack_head, hashtbl in_hash, char* in_line) 
 {
   char *temp, *rest;
@@ -263,6 +280,7 @@
   return 1;
 }
 
+/* Make a list. */
 extern void pack(stackitem** stack_head)
 {
   void* delimiter;
@@ -293,6 +311,7 @@
   push(stack_head, pack);
 }
 
+/* Push elements of the list on the stack. */
 extern void expand(stackitem** stack_head)
 {
   stackitem *temp, *new_head;
@@ -310,6 +329,7 @@
   *stack_head= new_head;
 }
 
+/* Swap the two top elements on the stack. */
 extern void swap(stackitem** stack_head)
 {
   stackitem* temp= (*stack_head);
@@ -322,6 +342,7 @@
   (*stack_head)->next= temp;
 } 
 
+/* Compares two elements by reference. */
 extern void eq(stackitem** stack_head)
 {
   void *left, *right;
@@ -339,6 +360,7 @@
   push_val(stack_head, (left==right));
 }
 
+/* Negates the top element on the stack. */
 extern void not(stackitem** stack_head)
 {
   int value;
@@ -351,12 +373,15 @@
   push_val(stack_head, !value);
 }
 
+/* Compares the two top elements on the stack and return 0 if they're the
+   same. */
 extern void neq(stackitem** stack_head)
 {
   eq(stack_head);
   not(stack_head);
 }
 
+/* Give a symbol some content. */
 extern void def(stackitem** stack_head)
 {
   stackitem *temp, *value;
@@ -374,6 +399,7 @@
   toss(stack_head); toss(stack_head);
 } 
 
+/* Quit stack. */
 extern void quit()
 {
   exit(EXIT_SUCCESS);