--- stack/stack.c	2002/02/08 05:37:54	1.61
+++ stack/stack.c	2002/02/08 06:23:19	1.62
@@ -955,15 +955,19 @@
   a=env->head->item->content.val;
   toss(env);
   if(env->err) return;
-  b=env->head->item->content.val;
-  toss(env);
-  if(env->err) return;
-  push_int(&(env->head), a+b);
+  if(env->head->item->refcount == 1)
+    env->head->item->content.val += a;
+  else {
+    b=env->head->item->content.val;
+    toss(env);
+    if(env->err) return;
+    push_int(&(env->head), a+b);
+  }
 }
 
 /* - */
 extern void sx_2d(environment *env) {
-  int a;
+  int a, b;
 
   if((env->head)==NULL || env->head->next==NULL) {
     printerr("Too Few Arguments");
@@ -980,12 +984,19 @@
   a=env->head->item->content.val;
   toss(env);
   if(env->err) return;
-  env->head->item->content.val -= a;
+  if(env->head->item->refcount == 1)
+    env->head->item->content.val -= a;
+  else {
+    b=env->head->item->content.val;
+    toss(env);
+    if(env->err) return;
+    push_int(&(env->head), b-a);
+  }
 }
 
 /* > */
 extern void sx_3e(environment *env) {
-  int a;
+  int a, b;
 
   if((env->head)==NULL || env->head->next==NULL) {
     printerr("Too Few Arguments");
@@ -1002,7 +1013,14 @@
   a=env->head->item->content.val;
   toss(env);
   if(env->err) return;
-  env->head->item->content.val = (env->head->item->content.val > a);
+  if(env->head->item->refcount == 1)
+    env->head->item->content.val = (env->head->item->content.val > a);
+  else {
+    b=env->head->item->content.val;
+    toss(env);
+    if(env->err) return;
+    push_int(&(env->head), b>a);
+  }
 }
 
 /* Return copy of a value */