--- stack/stack.c	2002/03/10 20:08:47	1.102
+++ stack/stack.c	2002/03/11 08:52:59	1.103
@@ -78,7 +78,7 @@
     return;
   }
   
-  env->head= env->head->cdr->content.c;	/* Remove the top stack item */
+  env->head= env->head->cdr->content.c; /* Remove the top stack item */
   free(temp);			/* Free the old top stack item */
 }
 
@@ -475,7 +475,7 @@
     break;
   case tcons:
     /* A list is just a stack, so make stack_head point to it */
-    stack_head=(cons*)(stack_head->car->content.ptr);
+    stack_head=stack_head->car->content.c;
     printf("[ ");
     while(stack_head != NULL) {
       print_h(stack_head, noquote);
@@ -567,7 +567,7 @@
   cons *temp= env->head;
   
   if(env->head==NULL || env->head->cdr->content.c==NULL
-      || env->head->cdr->content.c->cdr->content.c==NULL) {
+     || env->head->cdr->content.c->cdr->content.c==NULL) {
     printerr("Too Few Arguments");
     env->err=1;
     return;
@@ -660,13 +660,19 @@
 	toss(env);
 	if(env->err) return;
 	
-	if(iterator->cdr->content.c==NULL){
+	if(iterator->cdr->content.ptr==NULL){
 	  goto eval_start;
 	}
 	eval(env);
 	if(env->err) return;
       }
-      iterator= iterator->cdr->content.c;
+      if (iterator->cdr->type == tcons) 
+	iterator= iterator->cdr->content.c;
+      else {
+	printerr("Bad Argument Type"); /* Improper list */
+	env->err= 2;
+	return;
+      }
     }
     unprotect(temp_val);
     return;
@@ -693,7 +699,7 @@
     return;
   }
 
-  old_head= (cons*)(env->head->car->content.ptr);
+  old_head= env->head->car->content.c;
   new_head= NULL;
   while(old_head!=NULL) {
     item= old_head;
@@ -723,7 +729,7 @@
     /* Search for first delimiter */
     while(iterator->cdr->content.c!=NULL
 	  && (iterator->cdr->content.c->car->type!=symb
-	  || ((symbol*)(iterator->cdr->content.c->car->content.ptr))->id[0]
+	      || ((symbol*)(iterator->cdr->content.c->car->content.ptr))->id[0]
 	      !='['))
       iterator= iterator->cdr->content.c;
     
@@ -770,13 +776,20 @@
     return;
 
   /* The first list element is the new stack head */
-  new_head= temp= env->head->car->content.ptr;
+  new_head= temp= env->head->car->content.c;
 
   toss(env);
 
   /* Find the end of the list */
-  while(temp->cdr->content.c!=NULL)
-    temp= temp->cdr->content.c;
+  while(temp->cdr->content.ptr != NULL) {
+    if (temp->cdr->type == tcons)
+      temp= temp->cdr->content.c;
+    else {
+      printerr("Bad Argument Type"); /* Improper list */
+      env->err= 2;
+      return;
+    }
+  }
 
   /* Connect the tail of the list with the old stack head */
   temp->cdr->content.c= env->head;
@@ -987,7 +1000,7 @@
   }
 
   if(myenv.interactive) {
-    printf("Stack version $Revision: 1.102 $\n\
+    printf("Stack version $Revision: 1.103 $\n\
 Copyright (C) 2002  Mats Alritzson and Teddy Hogeborn\n\
 Stack comes with ABSOLUTELY NO WARRANTY; for details type `warranty;'.\n\
 This is free software, and you are welcome to redistribute it\n\
@@ -1269,22 +1282,13 @@
     new_value->content.ptr= NULL;
 
     prev_item= NULL;
-    old_item= (cons*)(old_value->content.ptr);
+    old_item= old_value->content.c;
 
-    while(old_item != NULL) {	/* While list is not empty */
+    if(old_value->content.ptr != NULL) { /* if list is not empty */
       new_item= malloc(sizeof(cons));
       new_item->car= copy_val(env, old_item->car); /* recurse */
-      new_item->cdr= new_val(env);
-      new_item->cdr->type= tcons;
-      new_item->cdr->content.c= NULL;
-      if(prev_item != NULL)	/* If this wasn't the first item */
-	prev_item->cdr->content.c= new_item; /* point the previous item to the
-                                     new item */
-      else
-	new_value->content.ptr= new_item;
-      old_item= old_item->cdr->content.c;
-      prev_item= new_item;
-    }	  
+      new_item->cdr= copy_val(env, old_item->cdr); /* recurse */
+    }
     break;
   }
 
@@ -1491,13 +1495,19 @@
   protect(foo);
   toss(env); if(env->err) return;
 
-  iterator= foo->content.ptr;
+  iterator= foo->content.c;
 
   while(iterator!=NULL) {
     push_val(env, iterator->car);
     push_val(env, loop);
     eval(env); if(env->err) return;
-    iterator= iterator->cdr->content.c;
+    if (iterator->cdr->type == tcons){
+      iterator= iterator->cdr->content.c;
+    } else {
+      printerr("Bad Argument Type"); /* Improper list */
+      env->err= 2;
+      break;
+    }
   }
   unprotect(loop); unprotect(foo);
 }
@@ -1543,16 +1553,16 @@
 
   if(iterator==NULL
      || (iterator->car->type==symb
-     && ((symbol*)(iterator->car->content.ptr))->id[0]=='[')) {
+	 && ((symbol*)(iterator->car->content.ptr))->id[0]=='[')) {
     temp= NULL;
     toss(env);
   } else {
     /* Search for first delimiter */
     while(iterator->cdr->content.c!=NULL
 	  && (iterator->cdr->content.c->car->type!=symb
-	  || ((symbol*)(iterator->cdr->content.c->car->content.ptr))->id[0]
+	      || ((symbol*)(iterator->cdr->content.c->car->content.ptr))->id[0]
 	      !='['))
-      iterator= iterator->cdr->content.c;
+      iterator= iterator->cdr->content.ptr;
     
     /* Extract list */
     temp= env->head;