Finally no nonsense is done with defconstant anymore.

diff --git a/constants.lisp b/constants.lisp
index c788c2d..40c5204 100755 (executable)
--- a/constants.lisp
+++ b/constants.lisp
@@ -2,10 +2,18 @@
 
 (in-package :uxul-world)
 
-(defconstant +screen-width+ 1024)
-(defconstant +screen-height+ 768)
+(defmacro mydefconst (x y)
+  `(eval-when (:compile-toplevel :load-toplevel)
+     (when (or (not (boundp ',x))
+              (not (equal ,y
+                          (symbol-value ',x))))
+       (defconstant ,x ,y))))
 
-(defconstant +class-indices+ '(t uxul-world::animation
+
+(mydefconst +screen-width+ 1024)
+(mydefconst +screen-height+ 768)
+
+(mydefconst +class-indices+ '(t uxul-world::animation
   uxul-world::collision uxul-world::game-object uxul-world::player
   uxul-world::room uxul-world::stone uxul-world::xy-coordinates
   uxul-world::bottom uxul-world::moving-enemy