--- stack/stack.c	2002/03/10 08:30:43	1.97
+++ stack/stack.c	2003/08/04 13:50:53	1.128
@@ -1,3 +1,4 @@
+/* -*- coding: utf-8; -*- */
 /*
     stack - an interactive interpreter for a stack-based language
     Copyright (C) 2002	Mats Alritzson and Teddy Hogeborn
@@ -20,27 +21,6 @@
 	     Teddy Hogeborn <teddy@fukt.bth.se>
 */
 
-/* printf, sscanf, fgets, fprintf, fopen, perror */
-#include <stdio.h>
-/* exit, EXIT_SUCCESS, malloc, free */
-#include <stdlib.h>
-/* NULL */
-#include <stddef.h>
-/* dlopen, dlsym, dlerror */
-#include <dlfcn.h>
-/* strcmp, strcpy, strlen, strcat, strdup */
-#include <string.h>
-/* getopt, STDIN_FILENO, STDOUT_FILENO, usleep */
-#include <unistd.h>
-/* EX_NOINPUT, EX_USAGE */
-#include <sysexits.h>
-/* mtrace, muntrace */
-#include <mcheck.h>
-/* ioctl */
-#include <sys/ioctl.h>
-/* KDMKTONE */
-#include <linux/kd.h>
-
 #include "stack.h"
 
 /* Initialize a newly created environment */
@@ -48,12 +28,11 @@
 {
   int i;
 
-  env->gc_limit= 200;
+  env->gc_limit= 400000;
   env->gc_count= 0;
   env->gc_ref= NULL;
-  env->gc_protect= NULL;
 
-  env->head= NULL;
+  env->head= new_val(env);
   for(i= 0; i<HASHTBLSIZE; i++)
     env->symbols[i]= NULL;
   env->err= 0;
@@ -68,23 +47,6 @@
   fprintf(stderr, "Err: %s\n", in_string);
 }
 
-/* Discard the top element of the stack. */
-extern void toss(environment *env)
-{
-  stackitem *temp= env->head;
-
-  if((env->head)==NULL) {
-    printerr("Too Few Arguments");
-    env->err= 1;
-    return;
-  }
-  
-  env->head= env->head->next;	/* Remove the top stack item */
-  free(temp);			/* Free the old top stack item */
-
-  env->gc_limit--;
-}
-
 /* Returns a pointer to a pointer to an element in the hash table. */
 symbol **hash(hashtbl in_hashtbl, const char *in_string)
 {
@@ -120,140 +82,194 @@
   value *nval= malloc(sizeof(value));
   stackitem *nitem= malloc(sizeof(stackitem));
 
+  assert(nval != NULL);
+  assert(nitem != NULL);
+
   nval->content.ptr= NULL;
+  nval->type= empty;
 
   nitem->item= nval;
   nitem->next= env->gc_ref;
+
   env->gc_ref= nitem;
 
-  env->gc_count++;
-  nval->gc_garb= 1;
+  env->gc_count += sizeof(value);
+  nval->gc.flag.mark= 0;
+  nval->gc.flag.protect= 0;
 
   return nval;
 }
 
+
 /* Mark values recursively. 
    Marked values are not collected by the GC. */
 inline void gc_mark(value *val)
 {
-  stackitem *iterator;
-
-  if(val->gc_garb==0)
+  if(val==NULL || val->gc.flag.mark)
     return;
 
-  val->gc_garb= 0;
-
-  if(val->type==list) {
-    iterator= val->content.ptr;
+  val->gc.flag.mark= 1;
 
-    while(iterator!=NULL) {
-      gc_mark(iterator->item);
-      iterator= iterator->next;
-    }
+  if(val->type==tcons) {
+    gc_mark(CAR(val));
+    gc_mark(CDR(val));
   }
 }
 
-inline void gc_maybe(environment *env)
-{
-  if(env->gc_count < env->gc_limit)
-    return;
-  else
-    return gc_init(env);
-}
 
 /* Start GC */
 extern void gc_init(environment *env)
 {
-  stackitem *new_head= NULL, *titem, *iterator;
+  stackitem *new_head= NULL, *titem;
   symbol *tsymb;
   int i;
 
-  /* Mark protected values */
-  iterator= env->gc_protect;
-  while(iterator!=NULL) {
-    gc_mark(iterator->item);
-    iterator= iterator->next;
-  }
+  if(env->interactive)
+    printf("Garbage collecting.");
 
   /* Mark values on stack */
-  iterator= env->head;
-  while(iterator!=NULL) {
-    gc_mark(iterator->item);
-    iterator= iterator->next;
-  }
+  gc_mark(env->head);
+
+  if(env->interactive)
+    printf(".");
+
 
   /* Mark values in hashtable */
-  for(i= 0; i<HASHTBLSIZE; i++) {
-    tsymb= env->symbols[i];
-    while(tsymb!=NULL) {
+  for(i= 0; i<HASHTBLSIZE; i++)
+    for(tsymb= env->symbols[i]; tsymb!=NULL; tsymb= tsymb->next)
       if (tsymb->val != NULL)
 	gc_mark(tsymb->val);
-      tsymb= tsymb->next;
-    }
-  }
+
+
+  if(env->interactive)
+    printf(".");
 
   env->gc_count= 0;
 
   while(env->gc_ref!=NULL) {	/* Sweep unused values */
 
-    if(env->gc_ref->item->gc_garb) {
+    if(!(env->gc_ref->item->gc.no_gc)){ /* neither mark nor protect */
 
-      switch(env->gc_ref->item->type) {	/* Remove content */
+      /* Remove content */
+      switch(env->gc_ref->item->type){
       case string:
 	free(env->gc_ref->item->content.ptr);
 	break;
-      case list:
-	while(env->gc_ref->item->content.ptr!=NULL) {
-	  titem= env->gc_ref->item->content.ptr;
-	  env->gc_ref->item->content.ptr= titem->next;
-	  free(titem);
-	}
-      default:
+      case tcons:
+	free(env->gc_ref->item->content.c);
+	break;
+      case port:
+      case empty:
+      case integer:
+      case tfloat:
+      case func:
+      case symb:
+	/* Symbol strings are freed when walking the hash table */
+	break;
       }
+
       free(env->gc_ref->item);	/* Remove from gc_ref */
       titem= env->gc_ref->next;
       free(env->gc_ref);	/* Remove value */
       env->gc_ref= titem;
       continue;
     }
+#ifdef DEBUG
+    printf("Kept value (%p)", env->gc_ref->item);
+    if(env->gc_ref->item->gc.flag.mark)
+      printf(" (marked)");
+    if(env->gc_ref->item->gc.flag.protect)
+      printf(" (protected)");
+    switch(env->gc_ref->item->type){
+    case integer:
+      printf(" integer: %d", env->gc_ref->item->content.i);
+      break;
+    case func:
+      printf(" func: %p", env->gc_ref->item->content.func);
+      break;
+    case symb:
+      printf(" symb: %s", env->gc_ref->item->content.sym->id);
+      break;
+    case tcons:
+      printf(" tcons: %p\t%p", CAR(env->gc_ref->item),
+	     CDR(env->gc_ref->item));
+      break;
+    default:
+      printf(" <unknown %d>", (env->gc_ref->item->type));
+    }
+    printf("\n");
+#endif /* DEBUG */
+
+    /* Keep values */     
+    env->gc_count += sizeof(value);
+    if(env->gc_ref->item->type==string)
+      env->gc_count += strlen(env->gc_ref->item->content.string)+1;
     
-    /* Keep values */
     titem= env->gc_ref->next;
     env->gc_ref->next= new_head;
     new_head= env->gc_ref;
-    new_head->item->gc_garb= 1;
+    new_head->item->gc.flag.mark= 0;
     env->gc_ref= titem;
-    env->gc_count++;
   }
 
-  env->gc_limit= env->gc_count*2;
+  if (env->gc_limit < env->gc_count*2)
+    env->gc_limit= env->gc_count*2;
+
   env->gc_ref= new_head;
+
+  if(env->interactive)
+    printf("done (%d bytes still allocated)\n", env->gc_count);
+
+}
+
+inline void gc_maybe(environment *env)
+{
+  if(env->gc_count < env->gc_limit)
+    return;
+  else
+    return gc_init(env);
 }
 
 /* Protect values from GC */
-void protect(environment *env, value *val)
+void protect(value *val)
 {
-  stackitem *new_item= malloc(sizeof(stackitem));
-  new_item->item= val;
-  new_item->next= env->gc_protect;
-  env->gc_protect= new_item;
+  if(val==NULL || val->gc.flag.protect)
+    return;
+
+  val->gc.flag.protect= 1;
+
+  if(val->type==tcons) {
+    protect(CAR(val));
+    protect(CDR(val));
+  }
 }
 
 /* Unprotect values from GC */
-void unprotect(environment *env)
+void unprotect(value *val)
 {
-  stackitem *temp= env->gc_protect;
-  env->gc_protect= env->gc_protect->next;
-  free(temp);
+  if(val==NULL || !(val->gc.flag.protect))
+    return;
+
+  val->gc.flag.protect= 0;
+
+  if(val->type==tcons) {
+    unprotect(CAR(val));
+    unprotect(CDR(val));
+  }
 }
 
 /* Push a value onto the stack */
 void push_val(environment *env, value *val)
 {
-  stackitem *new_item= malloc(sizeof(stackitem));
-  new_item->item= val;
-  new_item->next= env->head;
-  env->head= new_item;
+  value *new_value= new_val(env);
+
+  new_value->content.c= malloc(sizeof(pair));
+  assert(new_value->content.c!=NULL);
+  env->gc_count += sizeof(pair);
+  new_value->type= tcons;
+  CAR(new_value)= val;
+  CDR(new_value)= env->head;
+  env->head= new_value;
 }
 
 /* Push an integer onto the stack */
@@ -282,9 +298,12 @@
 void push_cstring(environment *env, const char *in_string)
 {
   value *new_value= new_val(env);
+  int length= strlen(in_string)+1;
 
-  new_value->content.ptr= malloc(strlen(in_string)+1);
-  strcpy(new_value->content.ptr, in_string);
+  new_value->content.string= malloc(length);
+  assert(new_value != NULL);
+  env->gc_count += length;
+  strcpy(new_value->content.string, in_string);
   new_value->type= string;
 
   push_val(env, new_value);
@@ -297,6 +316,7 @@
   char *new_string, *current;
 
   new_string= malloc((strlen(old_string)*2)+4);
+  assert(new_string != NULL);
   strcpy(new_string, "sx_");	/* Stack eXternal */
   current= new_string+3;
   while(old_string[0] != '\0'){
@@ -314,19 +334,19 @@
 {
   char *new_string;
 
-  if((env->head)==NULL) {
+  if(env->head->type==empty) {
     printerr("Too Few Arguments");
     env->err= 1;
     return;
   }
 
-  if(env->head->item->type!=string) {
+  if(CAR(env->head)->type!=string) {
     printerr("Bad Argument Type");
     env->err= 2;
     return;
   }
 
-  new_string= mangle_str((const char *)(env->head->item->content.ptr));
+  new_string= mangle_str(CAR(env->head)->content.string);
 
   toss(env);
   if(env->err) return;
@@ -350,9 +370,9 @@
   char *mangled;		/* Mangled function name */
 
   new_value= new_val(env);
-  protect(env, new_value);
+  protect(new_value);
   new_fvalue= new_val(env);
-  protect(env, new_fvalue);
+  protect(new_fvalue);
 
   /* The new value is a symbol */
   new_value->type= symb;
@@ -365,9 +385,11 @@
 
     /* Create a new symbol */
     (*new_symbol)= malloc(sizeof(symbol));
+    assert((*new_symbol) != NULL);
     (*new_symbol)->val= NULL;	/* undefined value */
     (*new_symbol)->next= NULL;
     (*new_symbol)->id= malloc(strlen(in_string)+1);
+    assert((*new_symbol)->id != NULL);
     strcpy((*new_symbol)->id, in_string);
 
     /* Intern the new symbol in the hash table */
@@ -389,7 +411,7 @@
 
     if(dlerr==NULL) {		/* If a function was found */
       new_fvalue->type= func;	/* The new value is a function pointer */
-      new_fvalue->content.ptr= funcptr; /* Store function pointer */
+      new_fvalue->content.func= funcptr; /* Store function pointer */
       (*new_symbol)->val= new_fvalue; /* Bind the symbol to the new
                                          function value */
     }
@@ -398,206 +420,207 @@
   }
 
   push_val(env, new_value);
-  unprotect(env); unprotect(env);
-}
-
-/* Print newline. */
-extern void nl()
-{
-  printf("\n");
+  unprotect(new_value); unprotect(new_fvalue);
 }
 
-/* Gets the type of a value */
-extern void type(environment *env)
+/* Print a value */
+void print_val(environment *env, value *val, int noquote, stackitem *stack, FILE *stream)
 {
-  int typenum;
+  stackitem *titem, *tstack;
+  int depth;
 
-  if((env->head)==NULL) {
-    printerr("Too Few Arguments");
-    env->err=1;
-    return;
-  }
-  typenum=env->head->item->type;
-  toss(env);
-  switch(typenum){
-  case integer:
-    push_sym(env, "integer");
-    break;
-  case tfloat:
-    push_sym(env, "float");
-    break;
-  case string:
-    push_sym(env, "string");
-    break;
-  case symb:
-    push_sym(env, "symbol");
-    break;
-  case func:
-    push_sym(env, "function");
-    break;
-  case list:
-    push_sym(env, "list");
+  switch(val->type) {
+  case empty:
+    if(fprintf(stream, "[]") < 0){
+      perror("print_val");
+      env->err= 5;
+      return;
+    }
     break;
-  }
-}    
-
-/* Prints the top element of the stack. */
-void print_h(stackitem *stack_head, int noquote)
-{
-  switch(stack_head->item->type) {
   case integer:
-    printf("%d", stack_head->item->content.i);
+    if(fprintf(stream, "%d", val->content.i) < 0){
+      perror("print_val");
+      env->err= 5;
+      return;
+    }
     break;
   case tfloat:
-    printf("%f", stack_head->item->content.f);
+    if(fprintf(stream, "%f", val->content.f) < 0){
+      perror("print_val");
+      env->err= 5;
+      return;
+    }
     break;
   case string:
-    if(noquote)
-      printf("%s", (char*)stack_head->item->content.ptr);
-    else
-      printf("\"%s\"", (char*)stack_head->item->content.ptr);
+    if(noquote){
+      if(fprintf(stream, "%s", val->content.string) < 0){
+	perror("print_val");
+	env->err= 5;
+	return;
+      }
+    } else {			/* quote */
+      if(fprintf(stream, "\"%s\"", val->content.string) < 0){
+	perror("print_val");
+	env->err= 5;
+	return;
+      }
+    }
     break;
   case symb:
-    printf("%s", ((symbol *)(stack_head->item->content.ptr))->id);
+    if(fprintf(stream, "%s", val->content.sym->id) < 0){
+      perror("print_val");
+      env->err= 5;
+      return;
+    }
     break;
   case func:
-    printf("#<function %p>", (funcp)(stack_head->item->content.ptr));
+    if(fprintf(stream, "#<function %p>", val->content.func) < 0){
+      perror("print_val");
+      env->err= 5;
+      return;
+    }
     break;
-  case list:
-    /* A list is just a stack, so make stack_head point to it */
-    stack_head=(stackitem *)(stack_head->item->content.ptr);
-    printf("[ ");
-    while(stack_head != NULL) {
-      print_h(stack_head, noquote);
-      printf(" ");
-      stack_head=stack_head->next;
+  case port:
+    if(fprintf(stream, "#<port %p>", val->content.p) < 0){
+      perror("print_val");
+      env->err= 5;
+      return;
     }
-    printf("]");
     break;
-  }
-}
-
-extern void print_(environment *env)
-{
-  if(env->head==NULL) {
-    printerr("Too Few Arguments");
-    env->err=1;
-    return;
-  }
-  print_h(env->head, 0);
-  nl();
-}
-
-/* Prints the top element of the stack and then discards it. */
-extern void print(environment *env)
-{
-  print_(env);
-  if(env->err) return;
-  toss(env);
-}
-
-extern void princ_(environment *env)
-{
-  if(env->head==NULL) {
-    printerr("Too Few Arguments");
-    env->err=1;
-    return;
-  }
-  print_h(env->head, 1);
-}
+  case tcons:
+    if(fprintf(stream, "[ ") < 0){
+      perror("print_val");
+      env->err= 5;
+      return;
+    }
+    tstack= stack;
+    do {
+      titem=malloc(sizeof(stackitem));
+      assert(titem != NULL);
+      titem->item=val;
+      titem->next=tstack;
+      tstack=titem;		/* Put it on the stack */
+      /* Search a stack of values being printed to see if we are already
+	 printing this value */
+      titem=tstack;
+      depth=0;
+      while(titem != NULL && titem->item != CAR(val)){
+	titem=titem->next;
+	depth++;
+      }
+      if(titem != NULL){	/* If we found it on the stack, */
+	if(fprintf(stream, "#%d#", depth) < 0){	/* print a depth reference */
+	  perror("print_val");
+	  env->err= 5;
+	  free(titem);
+	  return;
+	}
+      } else {
+	print_val(env, CAR(val), noquote, tstack, stream);
+      }
+      val= CDR(val);
+      switch(val->type){
+      case empty:
+	break;
+      case tcons:
+	/* Search a stack of values being printed to see if we are already
+	   printing this value */
+	titem=tstack;
+	depth=0;
+	while(titem != NULL && titem->item != val){
+	  titem=titem->next;
+	  depth++;
+	}
+	if(titem != NULL){	/* If we found it on the stack, */
+	  if(fprintf(stream, " . #%d#", depth) < 0){ /* print a depth reference */
+	    perror("print_val");
+	    env->err= 5;
+	    goto printval_end;
+	  }
+	} else {
+	  if(fprintf(stream, " ") < 0){
+	    perror("print_val");
+	    env->err= 5;
+	    goto printval_end;
+	  }
+	}
+	break;
+      default:
+	if(fprintf(stream, " . ") < 0){	/* Improper list */
+	  perror("print_val");
+	  env->err= 5;
+	  goto printval_end;
+        }
+	print_val(env, val, noquote, tstack, stream);
+      }
+    } while(val->type == tcons && titem == NULL);
 
-/* Prints the top element of the stack and then discards it. */
-extern void princ(environment *env)
-{
-  princ_(env);
-  if(env->err) return;
-  toss(env);
-}
+  printval_end:
 
-/* Only to be called by function printstack. */
-void print_st(stackitem *stack_head, long counter)
-{ 
-  if(stack_head->next != NULL)
-    print_st(stack_head->next, counter+1);
-  printf("%ld: ", counter);
-  print_h(stack_head, 0);
-  nl();
-}
+    titem=tstack;
+    while(titem != stack){
+      tstack=titem->next;
+      free(titem);
+      titem=tstack;
+    }
 
-/* Prints the stack. */
-extern void printstack(environment *env)
-{
-  if(env->head == NULL) {
-    printf("Stack Empty\n");
-    return;
+    if(! (env->err)){
+      if(fprintf(stream, " ]") < 0){
+	perror("print_val");
+	env->err= 5;
+      }
+    }
+    break;
   }
-
-  print_st(env->head, 1);
 }
 
 /* Swap the two top elements on the stack. */
 extern void swap(environment *env)
 {
-  stackitem *temp= env->head;
+  value *temp= env->head;
   
-  if(env->head==NULL || env->head->next==NULL) {
+  if(env->head->type == empty || CDR(env->head)->type == empty) {
     printerr("Too Few Arguments");
     env->err=1;
     return;
   }
 
-  env->head= env->head->next;
-  temp->next= env->head->next;
-  env->head->next= temp;
+  env->head= CDR(env->head);
+  CDR(temp)= CDR(env->head);
+  CDR(env->head)= temp;
 } 
 
-/* Rotate the first three elements on the stack. */
-extern void rot(environment *env)
-{
-  stackitem *temp= env->head;
-  
-  if(env->head==NULL || env->head->next==NULL
-      || env->head->next->next==NULL) {
-    printerr("Too Few Arguments");
-    env->err=1;
-    return;
-  }
-
-  env->head= env->head->next->next;
-  temp->next->next= env->head->next;
-  env->head->next= temp;
-}
-
 /* Recall a value from a symbol, if bound */
 extern void rcl(environment *env)
 {
   value *val;
 
-  if(env->head == NULL) {
+  if(env->head->type==empty) {
     printerr("Too Few Arguments");
-    env->err=1;
+    env->err= 1;
     return;
   }
 
-  if(env->head->item->type!=symb) {
+  if(CAR(env->head)->type!=symb) {
     printerr("Bad Argument Type");
-    env->err=2;
+    env->err= 2;
     return;
   }
 
-  val=((symbol *)(env->head->item->content.ptr))->val;
+  val= CAR(env->head)->content.sym->val;
   if(val == NULL){
     printerr("Unbound Variable");
-    env->err=3;
+    env->err= 3;
     return;
   }
-  protect(env, val);
-  toss(env);		/* toss the symbol */
+  push_val(env, val);		/* Return the symbol's bound value */
+  swap(env);
+  if(env->err) return;
+  toss(env);			/* toss the symbol */
   if(env->err) return;
-  push_val(env, val); /* Return its bound value */
-  unprotect(env);
 }
 
+
 /* If the top element is a symbol, determine if it's bound to a
    function value, and if it is, toss the symbol and execute the
    function. */
@@ -605,258 +628,104 @@
 {
   funcp in_func;
   value* temp_val;
-  stackitem* iterator;
+  value* iterator;
 
  eval_start:
 
   gc_maybe(env);
 
-  if(env->head==NULL) {
+  if(env->head->type==empty) {
     printerr("Too Few Arguments");
-    env->err=1;
+    env->err= 1;
     return;
   }
 
-  switch(env->head->item->type) {
+  switch(CAR(env->head)->type) {
     /* if it's a symbol */
   case symb:
     rcl(env);			/* get its contents */
     if(env->err) return;
-    if(env->head->item->type!=symb){ /* don't recurse symbols */
+    if(CAR(env->head)->type!=symb){ /* don't recurse symbols */
       goto eval_start;
     }
     return;
 
     /* If it's a lone function value, run it */
   case func:
-    in_func= (funcp)(env->head->item->content.ptr);
+    in_func= CAR(env->head)->content.func;
     toss(env); 
     if(env->err) return;
     return in_func(env);
 
     /* If it's a list */
-  case list:
-    temp_val= env->head->item;
-    protect(env, temp_val);
+  case tcons:
+    temp_val= CAR(env->head);
+    protect(temp_val);
 
     toss(env); if(env->err) return;
-    iterator= (stackitem*)temp_val->content.ptr;
+    iterator= temp_val;
     
-    while(iterator!=NULL) {
-      push_val(env, iterator->item);
+    while(iterator->type != empty) {
+      push_val(env, CAR(iterator));
       
-      if(env->head->item->type==symb
-	&& strcmp(";", ((symbol*)(env->head->item->content.ptr))->id)==0) {
+      if(CAR(env->head)->type==symb
+	 && CAR(env->head)->content.sym->id[0]==';') {
 	toss(env);
 	if(env->err) return;
 	
-	if(iterator->next == NULL){
+	if(CDR(iterator)->type == empty){
 	  goto eval_start;
 	}
 	eval(env);
 	if(env->err) return;
       }
-      iterator= iterator->next;
+      if (CDR(iterator)->type == empty || CDR(iterator)->type == tcons) 
+	iterator= CDR(iterator);
+      else {
+	printerr("Bad Argument Type"); /* Improper list */
+	env->err= 2;
+	return;
+      }
     }
-    unprotect(env);
+    unprotect(temp_val);
     return;
 
-  default:
-    return;
-  }
-}
-
-/* Reverse (flip) a list */
-extern void rev(environment *env)
-{
-  stackitem *old_head, *new_head, *item;
-
-  if((env->head)==NULL) {
-    printerr("Too Few Arguments");
-    env->err= 1;
-    return;
-  }
-
-  if(env->head->item->type!=list) {
-    printerr("Bad Argument Type");
-    env->err= 2;
-    return;
-  }
-
-  old_head= (stackitem *)(env->head->item->content.ptr);
-  new_head= NULL;
-  while(old_head != NULL){
-    item= old_head;
-    old_head= old_head->next;
-    item->next= new_head;
-    new_head= item;
-  }
-  env->head->item->content.ptr= new_head;
-}
-
-/* Make a list. */
-extern void pack(environment *env)
-{
-  stackitem *iterator, *temp;
-  value *pack;
-
-  iterator= env->head;
-  pack= new_val(env);
-  protect(env, pack);
-
-  if(iterator==NULL
-     || (iterator->item->type==symb
-     && ((symbol*)(iterator->item->content.ptr))->id[0]=='[')) {
-    temp= NULL;
-    toss(env);
-  } else {
-    /* Search for first delimiter */
-    while(iterator->next!=NULL
-	  && (iterator->next->item->type!=symb
-	  || ((symbol*)(iterator->next->item->content.ptr))->id[0]!='['))
-      iterator= iterator->next;
-    
-    /* Extract list */
-    temp= env->head;
-    env->head= iterator->next;
-    iterator->next= NULL;
-
-    pack->type= list;
-    pack->content.ptr= temp;
-    
-    if(env->head!=NULL)
-      toss(env);
-  }
-
-  /* Push list */
-
-  push_val(env, pack);
-  rev(env);
-
-  unprotect(env);
-}
-
-/* Relocate elements of the list on the stack. */
-extern void expand(environment *env)
-{
-  stackitem *temp, *new_head;
-
-  /* Is top element a list? */
-  if(env->head==NULL) {
-    printerr("Too Few Arguments");
-    env->err= 1;
-    return;
-  }
-  if(env->head->item->type!=list) {
-    printerr("Bad Argument Type");
-    env->err= 2;
+  case empty:
+    toss(env); 
+  case integer:
+  case tfloat:
+  case string:
+  case port:
     return;
   }
-
-  rev(env);
-
-  if(env->err)
-    return;
-
-  /* The first list element is the new stack head */
-  new_head= temp= env->head->item->content.ptr;
-
-  toss(env);
-
-  /* Find the end of the list */
-  while(temp->next!=NULL)
-    temp= temp->next;
-
-  /* Connect the tail of the list with the old stack head */
-  temp->next= env->head;
-  env->head= new_head;		/* ...and voila! */
-
 }
 
-/* Compares two elements by reference. */
-extern void eq(environment *env)
+/* List all defined words */
+extern void words(environment *env)
 {
-  void *left, *right;
-  int result;
-
-  if((env->head)==NULL || env->head->next==NULL) {
-    printerr("Too Few Arguments");
-    env->err= 1;
-    return;
-  }
-
-  left= env->head->item->content.ptr;
-  swap(env);
-  right= env->head->item->content.ptr;
-  result= (left==right);
+  symbol *temp;
+  int i;
   
-  toss(env); toss(env);
-  push_int(env, result);
-}
-
-/* Negates the top element on the stack. */
-extern void not(environment *env)
-{
-  int val;
-
-  if((env->head)==NULL) {
-    printerr("Too Few Arguments");
-    env->err= 1;
-    return;
-  }
-
-  if(env->head->item->type!=integer) {
-    printerr("Bad Argument Type");
-    env->err= 2;
-    return;
+  for(i= 0; i<HASHTBLSIZE; i++) {
+    temp= env->symbols[i];
+    while(temp!=NULL) {
+#ifdef DEBUG
+      if (temp->val != NULL && temp->val->gc.flag.protect)
+	printf("(protected) ");
+#endif /* DEBUG */
+      printf("%s ", temp->id);
+      temp= temp->next;
+    }
   }
-
-  val= env->head->item->content.i;
-  toss(env);
-  push_int(env, !val);
-}
-
-/* Compares the two top elements on the stack and return 0 if they're the
-   same. */
-extern void neq(environment *env)
-{
-  eq(env);
-  not(env);
 }
 
-/* Give a symbol some content. */
-extern void def(environment *env)
-{
-  symbol *sym;
-
-  /* Needs two values on the stack, the top one must be a symbol */
-  if(env->head==NULL || env->head->next==NULL) {
-    printerr("Too Few Arguments");
-    env->err= 1;
-    return;
-  }
-
-  if(env->head->item->type!=symb) {
-    printerr("Bad Argument Type");
-    env->err= 2;
-    return;
-  }
-
-  /* long names are a pain */
-  sym= env->head->item->content.ptr;
-
-  /* Bind the symbol to the value */
-  sym->val= env->head->next->item;
-
-  toss(env); toss(env);
-} 
-
 /* Quit stack. */
 extern void quit(environment *env)
 {
   int i;
 
-  clear(env);
+  while(env->head->type != empty)
+    toss(env);
 
   if (env->err) return;
   for(i= 0; i<HASHTBLSIZE; i++) {
@@ -869,36 +738,18 @@
   env->gc_limit= 0;
   gc_maybe(env);
 
+  words(env);
+
   if(env->free_string!=NULL)
     free(env->free_string);
   
+#ifdef __linux__
   muntrace();
+#endif
 
   exit(EXIT_SUCCESS);
 }
 
-/* Clear stack */
-extern void clear(environment *env)
-{
-  while(env->head!=NULL)
-    toss(env);
-}
-
-/* List all defined words */
-extern void words(environment *env)
-{
-  symbol *temp;
-  int i;
-  
-  for(i= 0; i<HASHTBLSIZE; i++) {
-    temp= env->symbols[i];
-    while(temp!=NULL) {
-      printf("%s\n", temp->id);
-      temp= temp->next;
-    }
-  }
-}
-
 /* Internal forget function */
 void forget_sym(symbol **hash_entry)
 {
@@ -911,34 +762,25 @@
   free(temp);
 }
 
-/* Forgets a symbol (remove it from the hash table) */
-extern void forget(environment *env)
-{
-  char* sym_id;
-  stackitem *stack_head= env->head;
+/* Only to be called by itself function printstack. */
+void print_st(environment *env, value *stack_head, long counter)
+{ 
+  if(CDR(stack_head)->type != empty)
+    print_st(env, CDR(stack_head), counter+1);
+  printf("%ld: ", counter);
+  print_val(env, CAR(stack_head), 0, NULL, stdout);
+  printf("\n");
+}
 
-  if(stack_head==NULL) {
-    printerr("Too Few Arguments");
-    env->err=1;
-    return;
-  }
-  
-  if(stack_head->item->type!=symb) {
-    printerr("Bad Argument Type");
-    env->err=2;
+/* Prints the stack. */
+extern void printstack(environment *env)
+{
+  if(env->head->type == empty) {
+    printf("Stack Empty\n");
     return;
   }
 
-  sym_id= ((symbol*)(stack_head->item->content.ptr))->id;
-  toss(env);
-
-  return forget_sym(hash(env->symbols, sym_id));
-}
-
-/* Returns the current error number to the stack */
-extern void errn(environment *env)
-{
-  push_int(env, env->err);
+  print_st(env, env->head, 1);
 }
 
 int main(int argc, char **argv)
@@ -947,7 +789,9 @@
 
   int c;			/* getopt option character */
 
+#ifdef __linux__
   mtrace();
+#endif
 
   init_env(&myenv);
 
@@ -961,7 +805,7 @@
 	break;
       case '?':
 	fprintf (stderr,
-		 "Unknown option character `\\x%x'.\n",
+		 "Unknown option character '\\x%x'.\n",
 		 optopt);
 	return EX_USAGE;
       default:
@@ -978,11 +822,11 @@
   }
 
   if(myenv.interactive) {
-    printf("Stack version $Revision: 1.97 $\n\
+    printf("Stack version $Revision: 1.128 $\n\
 Copyright (C) 2002  Mats Alritzson and Teddy Hogeborn\n\
-Stack comes with ABSOLUTELY NO WARRANTY; for details type `warranty;'.\n\
+Stack comes with ABSOLUTELY NO WARRANTY; for details type 'warranty;'.\n\
 This is free software, and you are welcome to redistribute it\n\
-under certain conditions; type `copying;' for details.\n");
+under certain conditions; type 'copying;' for details.\n");
   }
 
   while(1) {
@@ -990,259 +834,40 @@
       if (myenv.interactive) {
 	if(myenv.err) {
 	  printf("(error %d)\n", myenv.err);
+	  myenv.err= 0;
 	}
-	nl();
+	printf("\n");
 	printstack(&myenv);
 	printf("> ");
       }
       myenv.err=0;
     }
-    sx_72656164(&myenv);
-    if (myenv.err==4) {
-      return EXIT_SUCCESS;	/* EOF */
-    } else if(myenv.head!=NULL
-	      && myenv.head->item->type==symb
-	      && ((symbol*)(myenv.head->item->content.ptr))->id[0]==';') {
-      toss(&myenv); 		/* No error check in main */
+    readstream(&myenv, myenv.inputstream);
+    if (myenv.err) {		/* EOF or other error */
+      myenv.err=0;
+      quit(&myenv);
+    } else if(myenv.head->type!=empty
+	      && CAR(myenv.head)->type==symb
+	      && CAR(myenv.head)->content.sym->id[0] == ';') {
+      toss(&myenv); if(myenv.err) continue;
       eval(&myenv);
+    } else {
+      gc_maybe(&myenv);
     }
-    gc_maybe(&myenv);
   }
   quit(&myenv);
   return EXIT_FAILURE;
 }
 
-/* "+" */
-extern void sx_2b(environment *env)
-{
-  int a, b;
-  float fa, fb;
-  size_t len;
-  char* new_string;
-  value *a_val, *b_val;
-
-  if((env->head)==NULL || env->head->next==NULL) {
-    printerr("Too Few Arguments");
-    env->err= 1;
-    return;
-  }
-
-  if(env->head->item->type==string
-     && env->head->next->item->type==string) {
-    a_val= env->head->item;
-    b_val= env->head->next->item;
-    protect(env, a_val); protect(env, b_val);
-    toss(env); if(env->err) return;
-    toss(env); if(env->err) return;
-    len= strlen(a_val->content.ptr)+strlen(b_val->content.ptr)+1;
-    new_string= malloc(len);
-    strcpy(new_string, b_val->content.ptr);
-    strcat(new_string, a_val->content.ptr);
-    push_cstring(env, new_string);
-    unprotect(env); unprotect(env);
-    free(new_string);
-    
-    return;
-  }
-  
-  if(env->head->item->type==integer
-     && env->head->next->item->type==integer) {
-    a=env->head->item->content.i;
-    toss(env); if(env->err) return;
-    b=env->head->item->content.i;
-    toss(env); if(env->err) return;
-    push_int(env, b+a);
-
-    return;
-  }
-
-  if(env->head->item->type==tfloat
-     && env->head->next->item->type==tfloat) {
-    fa= env->head->item->content.f;
-    toss(env); if(env->err) return;
-    fb= env->head->item->content.f;
-    toss(env); if(env->err) return;
-    push_float(env, fb+fa);
-    
-    return;
-  }
-
-  if(env->head->item->type==tfloat
-     && env->head->next->item->type==integer) {
-    fa= env->head->item->content.f;
-    toss(env); if(env->err) return;
-    b= env->head->item->content.i;
-    toss(env); if(env->err) return;
-    push_float(env, b+fa);
-    
-    return;
-  }
-
-  if(env->head->item->type==integer
-     && env->head->next->item->type==tfloat) {
-    a= env->head->item->content.i;
-    toss(env); if(env->err) return;
-    fb= env->head->item->content.f;
-    toss(env); if(env->err) return;
-    push_float(env, fb+a);
-
-    return;
-  }
-
-  printerr("Bad Argument Type");
-  env->err=2;
-}
-
-/* "-" */
-extern void sx_2d(environment *env)
-{
-  int a, b;
-  float fa, fb;
-
-  if((env->head)==NULL || env->head->next==NULL) {
-    printerr("Too Few Arguments");
-    env->err=1;
-    return;
-  }
-  
-  if(env->head->item->type==integer
-     && env->head->next->item->type==integer) {
-    a=env->head->item->content.i;
-    toss(env); if(env->err) return;
-    b=env->head->item->content.i;
-    toss(env); if(env->err) return;
-    push_int(env, b-a);
-
-    return;
-  }
-
-  if(env->head->item->type==tfloat
-     && env->head->next->item->type==tfloat) {
-    fa= env->head->item->content.f;
-    toss(env); if(env->err) return;
-    fb= env->head->item->content.f;
-    toss(env); if(env->err) return;
-    push_float(env, fb-fa);
-    
-    return;
-  }
-
-  if(env->head->item->type==tfloat
-     && env->head->next->item->type==integer) {
-    fa= env->head->item->content.f;
-    toss(env); if(env->err) return;
-    b= env->head->item->content.i;
-    toss(env); if(env->err) return;
-    push_float(env, b-fa);
-    
-    return;
-  }
-
-  if(env->head->item->type==integer
-     && env->head->next->item->type==tfloat) {
-    a= env->head->item->content.i;
-    toss(env); if(env->err) return;
-    fb= env->head->item->content.f;
-    toss(env); if(env->err) return;
-    push_float(env, fb-a);
-
-    return;
-  }
-
-  printerr("Bad Argument Type");
-  env->err=2;
-}
-
-/* ">" */
-extern void sx_3e(environment *env)
-{
-  int a, b;
-  float fa, fb;
-
-  if((env->head)==NULL || env->head->next==NULL) {
-    printerr("Too Few Arguments");
-    env->err=1;
-    return;
-  }
-  
-  if(env->head->item->type==integer
-     && env->head->next->item->type==integer) {
-    a=env->head->item->content.i;
-    toss(env); if(env->err) return;
-    b=env->head->item->content.i;
-    toss(env); if(env->err) return;
-    push_int(env, b>a);
-
-    return;
-  }
-
-  if(env->head->item->type==tfloat
-     && env->head->next->item->type==tfloat) {
-    fa= env->head->item->content.f;
-    toss(env); if(env->err) return;
-    fb= env->head->item->content.f;
-    toss(env); if(env->err) return;
-    push_int(env, fb>fa);
-    
-    return;
-  }
-
-  if(env->head->item->type==tfloat
-     && env->head->next->item->type==integer) {
-    fa= env->head->item->content.f;
-    toss(env); if(env->err) return;
-    b= env->head->item->content.i;
-    toss(env); if(env->err) return;
-    push_int(env, b>fa);
-    
-    return;
-  }
-
-  if(env->head->item->type==integer
-     && env->head->next->item->type==tfloat) {
-    a= env->head->item->content.i;
-    toss(env); if(env->err) return;
-    fb= env->head->item->content.f;
-    toss(env); if(env->err) return;
-    push_int(env, fb>a);
-
-    return;
-  }
-
-  printerr("Bad Argument Type");
-  env->err=2;
-}
-
-/* "<" */
-extern void sx_3c(environment *env) 
-{
-  swap(env); if(env->err) return;
-  sx_3e(env);
-}
-
-/* "<=" */
-extern void sx_3c3d(environment *env)
-{
-  sx_3e(env); if(env->err) return;
-  not(env);
-}
-
-/* ">=" */
-extern void sx_3e3d(environment *env)
-{
-  sx_3c(env); if(env->err) return;
-  not(env);
-}
-
 /* Return copy of a value */
 value *copy_val(environment *env, value *old_value)
 {
-  stackitem *old_item, *new_item, *prev_item;
   value *new_value;
 
-  protect(env, old_value);
+  if(old_value==NULL)
+    return NULL;
+
   new_value= new_val(env);
-  protect(env, new_value);
   new_value->type= old_value->type;
 
   switch(old_value->type){
@@ -1250,330 +875,111 @@
   case integer:
   case func:
   case symb:
+  case empty:
+  case port:
     new_value->content= old_value->content;
     break;
   case string:
-    (char *)(new_value->content.ptr)= 
-      strdup((char *)(old_value->content.ptr));
+    new_value->content.string= strdup(old_value->content.string);
     break;
-  case list:
-    new_value->content.ptr= NULL;
+  case tcons:
 
-    prev_item= NULL;
-    old_item= (stackitem*)(old_value->content.ptr);
+    new_value->content.c= malloc(sizeof(pair));
+    assert(new_value->content.c!=NULL);
+    env->gc_count += sizeof(pair);
 
-    while(old_item != NULL) {	/* While list is not empty */
-      new_item= malloc(sizeof(stackitem));
-      new_item->item= copy_val(env, old_item->item); /* recurse */
-      new_item->next= NULL;
-      if(prev_item != NULL)	/* If this wasn't the first item */
-	prev_item->next= new_item; /* point the previous item to the
-                                     new item */
-      else
-	new_value->content.ptr= new_item;
-      old_item= old_item->next;
-      prev_item= new_item;
-    }	  
+    CAR(new_value)= copy_val(env, CAR(old_value)); /* recurse */
+    CDR(new_value)= copy_val(env, CDR(old_value)); /* recurse */
     break;
   }
 
-  unprotect(env); unprotect(env);
-
   return new_value;
 }
 
-/* "dup"; duplicates an item on the stack */
-extern void sx_647570(environment *env)
+/* read a line from a stream; used by readline */
+void readlinestream(environment *env, FILE *stream)
 {
-  if((env->head)==NULL) {
-    printerr("Too Few Arguments");
-    env->err= 1;
-    return;
-  }
-  push_val(env, copy_val(env, env->head->item));
-}
-
-/* "if", If-Then */
-extern void sx_6966(environment *env)
-{
-  int truth;
-
-  if((env->head)==NULL || env->head->next==NULL) {
-    printerr("Too Few Arguments");
-    env->err= 1;
-    return;
-  }
-
-  if(env->head->next->item->type != integer) {
-    printerr("Bad Argument Type");
-    env->err=2;
-    return;
-  }
-  
-  swap(env);
-  if(env->err) return;
-  
-  truth=env->head->item->content.i;
-
-  toss(env);
-  if(env->err) return;
-
-  if(truth)
-    eval(env);
-  else
-    toss(env);
-}
-
-/* If-Then-Else */
-extern void ifelse(environment *env)
-{
-  int truth;
-
-  if((env->head)==NULL || env->head->next==NULL
-     || env->head->next->next==NULL) {
-    printerr("Too Few Arguments");
-    env->err=1;
-    return;
-  }
-
-  if(env->head->next->next->item->type != integer) {
-    printerr("Bad Argument Type");
-    env->err=2;
-    return;
-  }
-  
-  rot(env);
-  if(env->err) return;
-  
-  truth=env->head->item->content.i;
-
-  toss(env);
-  if(env->err) return;
-
-  if(!truth)
-    swap(env);
-  if(env->err) return;
-
-  toss(env);
-  if(env->err) return;
-
-  eval(env);
-}
-
-/* "while" */
-extern void sx_7768696c65(environment *env)
-{
-  int truth;
-  value *loop, *test;
-
-  if((env->head)==NULL || env->head->next==NULL) {
-    printerr("Too Few Arguments");
-    env->err=1;
-    return;
-  }
-
-  loop= env->head->item;
-  protect(env, loop);
-  toss(env); if(env->err) return;
-
-  test= env->head->item;
-  protect(env, test);
-  toss(env); if(env->err) return;
+  char in_string[101];
 
-  do {
-    push_val(env, test);
-    eval(env);
-    
-    if(env->head->item->type != integer) {
-      printerr("Bad Argument Type");
-      env->err= 2;
-      return;
-    }
-    
-    truth= env->head->item->content.i;
-    toss(env); if(env->err) return;
-    
-    if(truth) {
-      push_val(env, loop);
-      eval(env);
-    } else {
-      toss(env);
+  if(fgets(in_string, 100, stream)==NULL) {
+    push_cstring(env, "");
+    if (! feof(stream)){
+      perror("readline");
+      env->err= 5;
     }
-  
-  } while(truth);
-
-  unprotect(env); unprotect(env);
+  } else {
+    push_cstring(env, in_string);
+  }
 }
 
-
-/* "for"; for-loop */
-extern void sx_666f72(environment *env)
+/* Reverse (flip) a list */
+extern void rev(environment *env)
 {
-  value *loop;
-  int foo1, foo2;
+  value *old_head, *new_head, *item;
 
-  if(env->head==NULL || env->head->next==NULL 
-     || env->head->next->next==NULL) {
+  if(env->head->type==empty) {
     printerr("Too Few Arguments");
     env->err= 1;
     return;
   }
 
-  if(env->head->next->item->type!=integer
-     || env->head->next->next->item->type!=integer) {
-    printerr("Bad Argument Type");
-    env->err= 2;
-    return;
-  }
+  if(CAR(env->head)->type==empty)
+    return;			/* Don't reverse an empty list */
 
-  loop= env->head->item;
-  protect(env, loop);
-  toss(env); if(env->err) return;
-
-  foo2= env->head->item->content.i;
-  toss(env); if(env->err) return;
-
-  foo1= env->head->item->content.i;
-  toss(env); if(env->err) return;
-
-  if(foo1<=foo2) {
-    while(foo1<=foo2) {
-      push_int(env, foo1);
-      push_val(env, loop);
-      eval(env); if(env->err) return;
-      foo1++;
-    }
-  } else {
-    while(foo1>=foo2) {
-      push_int(env, foo1);
-      push_val(env, loop);
-      eval(env); if(env->err) return;
-      foo1--;
-    }
-  }
-  unprotect(env);
-}
-
-/* Variant of for-loop */
-extern void foreach(environment *env)
-{  
-  value *loop, *foo;
-  stackitem *iterator;
-  
-  if((env->head)==NULL || env->head->next==NULL) {
-    printerr("Too Few Arguments");
-    env->err= 1;
-    return;
-  }
-
-  if(env->head->next->item->type != list) {
+  if(CAR(env->head)->type!=tcons) {
     printerr("Bad Argument Type");
     env->err= 2;
     return;
   }
 
-  loop= env->head->item;
-  protect(env, loop);
-  toss(env); if(env->err) return;
-
-  foo= env->head->item;
-  protect(env, foo);
-  toss(env); if(env->err) return;
-
-  iterator= foo->content.ptr;
-
-  while(iterator!=NULL) {
-    push_val(env, iterator->item);
-    push_val(env, loop);
-    eval(env); if(env->err) return;
-    iterator= iterator->next;
+  old_head= CAR(env->head);
+  new_head= new_val(env);
+  while(old_head->type != empty) {
+    item= old_head;
+    old_head= CDR(old_head);
+    CDR(item)= new_head;
+    new_head= item;
   }
-  unprotect(env); unprotect(env);
+  CAR(env->head)= new_head;
 }
 
-/* "to" */
-extern void to(environment *env)
+/* Make a list. */
+extern void pack(environment *env)
 {
-  int ending, start, i;
-  stackitem *iterator, *temp;
-  value *pack;
+  value *iterator, *temp, *ending;
 
-  if((env->head)==NULL || env->head->next==NULL) {
-    printerr("Too Few Arguments");
-    env->err=1;
-    return;
-  }
-
-  if(env->head->item->type!=integer 
-     || env->head->next->item->type!=integer) {
-    printerr("Bad Argument Type");
-    env->err=2;
-    return;
-  }
-
-  ending= env->head->item->content.i;
-  toss(env); if(env->err) return;
-  start= env->head->item->content.i;
-  toss(env); if(env->err) return;
-
-  push_sym(env, "[");
-
-  if(ending>=start) {
-    for(i= ending; i>=start; i--)
-      push_int(env, i);
-  } else {
-    for(i= ending; i<=start; i++)
-      push_int(env, i);
-  }
+  ending=new_val(env);
 
   iterator= env->head;
-  pack= new_val(env);
-  protect(env, pack);
-
-  if(iterator==NULL
-     || (iterator->item->type==symb
-     && ((symbol*)(iterator->item->content.ptr))->id[0]=='[')) {
-    temp= NULL;
+  if(iterator->type == empty
+     || (CAR(iterator)->type==symb
+     && CAR(iterator)->content.sym->id[0]=='[')) {
+    temp= ending;
     toss(env);
   } else {
     /* Search for first delimiter */
-    while(iterator->next!=NULL
-	  && (iterator->next->item->type!=symb
-	  || ((symbol*)(iterator->next->item->content.ptr))->id[0]!='['))
-      iterator= iterator->next;
+    while(CDR(iterator)->type != empty
+	  && (CAR(CDR(iterator))->type!=symb
+	   || CAR(CDR(iterator))->content.sym->id[0]!='['))
+      iterator= CDR(iterator);
     
     /* Extract list */
     temp= env->head;
-    env->head= iterator->next;
-    iterator->next= NULL;
+    env->head= CDR(iterator);
+    CDR(iterator)= ending;
 
-    pack->type= list;
-    pack->content.ptr= temp;
-    
-    if(env->head!=NULL)
+    if(env->head->type != empty)
       toss(env);
   }
 
   /* Push list */
 
-  push_val(env, pack);
-
-  unprotect(env);
-}
-
-/* Read a string */
-extern void readline(environment *env)
-{
-  char in_string[101];
-
-  if(fgets(in_string, 100, env->inputstream)==NULL)
-    push_cstring(env, "");
-  else
-    push_cstring(env, in_string);
+  push_val(env, temp);
+  rev(env);
 }
 
-/* "read"; Read a value and place on stack */
-extern void sx_72656164(environment *env)
+/* read from a stream; used by "read" and "readport" */
+void readstream(environment *env, FILE *stream)
 {
   const char symbform[]= "%[a-zA-Z0-9!$%*+./:<=>?@^_~-]%n";
   const char strform[]= "\"%[^\"]\"%n";
@@ -1588,28 +994,31 @@
   int count= -1;
   float ftemp;
   static int depth= 0;
-  char *match, *ctemp;
+  char *match;
   size_t inlength;
 
   if(env->in_string==NULL) {
     if(depth > 0 && env->interactive) {
       printf("]> ");
     }
-    readline(env); if(env->err) return;
+    readlinestream(env, env->inputstream);
+    if(env->err) return;
 
-    if(((char *)(env->head->item->content.ptr))[0]=='\0'){
+    if((CAR(env->head)->content.string)[0]=='\0'){
       env->err= 4;		/* "" means EOF */
       return;
     }
     
-    env->in_string= malloc(strlen(env->head->item->content.ptr)+1);
+    env->in_string= malloc(strlen(CAR(env->head)->content.string)+1);
+    assert(env->in_string != NULL);
     env->free_string= env->in_string; /* Save the original pointer */
-    strcpy(env->in_string, env->head->item->content.ptr);
+    strcpy(env->in_string, CAR(env->head)->content.string);
     toss(env); if(env->err) return;
   }
   
   inlength= strlen(env->in_string)+1;
   match= malloc(inlength);
+  assert(match != NULL);
 
   if(sscanf(env->in_string, blankform, &readlength) != EOF
      && readlength != -1) {
@@ -1622,6 +1031,9 @@
     } else {
       push_float(env, ftemp);
     }
+  } else if(sscanf(env->in_string, "\"\"%n", &readlength) != EOF
+	    && readlength != -1) {
+    push_cstring(env, "");
   } else if(sscanf(env->in_string, strform, match, &readlength) != EOF
 	    && readlength != -1) {
     push_cstring(env, match);
@@ -1650,78 +1062,12 @@
   free(match);
 
   if(depth)
-    return sx_72656164(env);
-}
-
-extern void beep(environment *env)
-{
-  int freq, dur, period, ticks;
-
-  if((env->head)==NULL || env->head->next==NULL) {
-    printerr("Too Few Arguments");
-    env->err=1;
-    return;
-  }
-
-  if(env->head->item->type!=integer
-     || env->head->next->item->type!=integer) {
-    printerr("Bad Argument Type");
-    env->err=2;
-    return;
-  }
-
-  dur=env->head->item->content.i;
-  toss(env);
-  freq=env->head->item->content.i;
-  toss(env);
-
-  period=1193180/freq;		/* convert freq from Hz to period
-                                   length */
-  ticks=dur*.001193180;		/* convert duration from µseconds to
-				   timer ticks */
-
-/*    ticks=dur/1000; */
-
-  /*  if (ioctl(STDOUT_FILENO, KDMKTONE, (125<<16) + 0x637)==0) */
-  switch (ioctl(STDOUT_FILENO, KDMKTONE, (ticks<<16) | period)){
-  case 0:
-    usleep(dur);
-    return;
-  case -1:
-    perror("beep");
-    env->err=5;
-    return;
-  default:
-    abort();
-  }
-}
-
-/* "wait" */
-extern void sx_77616974(environment *env)
-{
-  int dur;
-
-  if((env->head)==NULL) {
-    printerr("Too Few Arguments");
-    env->err=1;
-    return;
-  }
-
-  if(env->head->item->type!=integer) {
-    printerr("Bad Argument Type");
-    env->err=2;
-    return;
-  }
-
-  dur=env->head->item->content.i;
-  toss(env);
-
-  usleep(dur);
+    return readstream(env, env->inputstream);
 }
 
 extern void copying(environment *env)
 {
-  printf("GNU GENERAL PUBLIC LICENSE\n\
+  printf("		    GNU GENERAL PUBLIC LICENSE\n\
 		       Version 2, June 1991\n\
 \n\
  Copyright (C) 1989, 1991 Free Software Foundation, Inc.\n\
@@ -2004,174 +1350,85 @@
 POSSIBILITY OF SUCH DAMAGES.\n");
 }
 
-/* "*" */
-extern void sx_2a(environment *env)
+/* General assoc function */
+void assocgen(environment *env, funcp eqfunc)
 {
-  int a, b;
-  float fa, fb;
+  value *key, *item;
 
-  if((env->head)==NULL || env->head->next==NULL) {
+  /* Needs two values on the stack, the top one must be an association
+     list */
+  if(env->head->type==empty || CDR(env->head)->type==empty) {
     printerr("Too Few Arguments");
-    env->err=1;
-    return;
-  }
-  
-  if(env->head->item->type==integer
-     && env->head->next->item->type==integer) {
-    a=env->head->item->content.i;
-    toss(env); if(env->err) return;
-    b=env->head->item->content.i;
-    toss(env); if(env->err) return;
-    push_int(env, b*a);
-
-    return;
-  }
-
-  if(env->head->item->type==tfloat
-     && env->head->next->item->type==tfloat) {
-    fa= env->head->item->content.f;
-    toss(env); if(env->err) return;
-    fb= env->head->item->content.f;
-    toss(env); if(env->err) return;
-    push_float(env, fb*fa);
-    
+    env->err= 1;
     return;
   }
 
-  if(env->head->item->type==tfloat
-     && env->head->next->item->type==integer) {
-    fa= env->head->item->content.f;
-    toss(env); if(env->err) return;
-    b= env->head->item->content.i;
-    toss(env); if(env->err) return;
-    push_float(env, b*fa);
-    
+  if(CAR(env->head)->type!=tcons) {
+    printerr("Bad Argument Type");
+    env->err= 2;
     return;
   }
 
-  if(env->head->item->type==integer
-     && env->head->next->item->type==tfloat) {
-    a= env->head->item->content.i;
-    toss(env); if(env->err) return;
-    fb= env->head->item->content.f;
-    toss(env); if(env->err) return;
-    push_float(env, fb*a);
+  key=CAR(CDR(env->head));
+  item=CAR(env->head);
 
+  while(item->type == tcons){
+    if(CAR(item)->type != tcons){
+      printerr("Bad Argument Type");
+      env->err= 2;
+      return;
+    }
+    push_val(env, key);
+    push_val(env, CAR(CAR(item)));
+    eqfunc(env); if(env->err) return;
+
+    /* Check the result of 'eqfunc' */
+    if(env->head->type==empty) {
+      printerr("Too Few Arguments");
+      env->err= 1;
     return;
-  }
-
-  printerr("Bad Argument Type");
-  env->err=2;
-}
-
-/* "/" */
-extern void sx_2f(environment *env)
-{
-  int a, b;
-  float fa, fb;
+    }
+    if(CAR(env->head)->type!=integer) {
+      printerr("Bad Argument Type");
+      env->err= 2;
+      return;
+    }
 
-  if((env->head)==NULL || env->head->next==NULL) {
-    printerr("Too Few Arguments");
-    env->err=1;
-    return;
-  }
-  
-  if(env->head->item->type==integer
-     && env->head->next->item->type==integer) {
-    a=env->head->item->content.i;
-    toss(env); if(env->err) return;
-    b=env->head->item->content.i;
+    if(CAR(env->head)->content.i){
+      toss(env); if(env->err) return;
+      break;
+    }
     toss(env); if(env->err) return;
-    push_float(env, b/a);
 
-    return;
-  }
-
-  if(env->head->item->type==tfloat
-     && env->head->next->item->type==tfloat) {
-    fa= env->head->item->content.f;
-    toss(env); if(env->err) return;
-    fb= env->head->item->content.f;
-    toss(env); if(env->err) return;
-    push_float(env, fb/fa);
-    
-    return;
-  }
+    if(item->type!=tcons) {
+      printerr("Bad Argument Type");
+      env->err= 2;
+      return;
+    }
 
-  if(env->head->item->type==tfloat
-     && env->head->next->item->type==integer) {
-    fa= env->head->item->content.f;
-    toss(env); if(env->err) return;
-    b= env->head->item->content.i;
-    toss(env); if(env->err) return;
-    push_float(env, b/fa);
-    
-    return;
+    item=CDR(item);
   }
 
-  if(env->head->item->type==integer
-     && env->head->next->item->type==tfloat) {
-    a= env->head->item->content.i;
-    toss(env); if(env->err) return;
-    fb= env->head->item->content.f;
-    toss(env); if(env->err) return;
-    push_float(env, fb/a);
-
-    return;
+  if(item->type == tcons){	/* A match was found */
+    push_val(env, CAR(item));
+  } else {
+    push_int(env, 0);
   }
-
-  printerr("Bad Argument Type");
-  env->err=2;
+  swap(env); if(env->err) return;
+  toss(env); if(env->err) return;
+  swap(env); if(env->err) return;
+  toss(env);
 }
 
-/* "mod" */
-extern void mod(environment *env)
+/* Discard the top element of the stack. */
+extern void toss(environment *env)
 {
-  int a, b;
-
-  if((env->head)==NULL || env->head->next==NULL) {
+  if(env->head->type==empty) {
     printerr("Too Few Arguments");
     env->err= 1;
     return;
   }
   
-  if(env->head->item->type==integer
-     && env->head->next->item->type==integer) {
-    a= env->head->item->content.i;
-    toss(env); if(env->err) return;
-    b= env->head->item->content.i;
-    toss(env); if(env->err) return;
-    push_int(env, b%a);
-
-    return;
-  }
-
-  printerr("Bad Argument Type");
-  env->err=2;
+  env->head= CDR(env->head); /* Remove the top stack item */
 }
 
-/* "div" */
-extern void sx_646976(environment *env)
-{
-  int a, b;
-  
-  if((env->head)==NULL || env->head->next==NULL) {
-    printerr("Too Few Arguments");
-    env->err= 1;
-    return;
-  }
-
-  if(env->head->item->type==integer
-     && env->head->next->item->type==integer) {
-    a= env->head->item->content.i;
-    toss(env); if(env->err) return;
-    b= env->head->item->content.i;
-    toss(env); if(env->err) return;
-    push_int(env, (int)b/a);
-
-    return;
-  }
-
-  printerr("Bad Argument Type");
-  env->err= 2;
-}