1 files changed, 8 insertions, 7 deletions
diff --git a/def.lisp b/def.lisp
index 65fd695..055a30b 100644
--- a/def.lisp
+++ b/def.lisp
@@ -19,13 +19,14 @@ easily document uninitialized special variables."
 reevaluated."
   (assert (good-muffed-var-name-p name :muffer "+"))
   (let ((newval (gensym "NEWVAL-")))
-   `(let ((,newval ,value))
-      (handler-bind ((error
-                       (lambda (&rest ignore)
-                         (declare (ignore ignore))
-                         (invoke-restart 'cl:continue))))
-        (makunbound ',name))
-      (defconstant ,name ,newval ,@(when doc (list doc))))))
+   `(eval-when (:compile-toplevel :load-toplevel :execute)
+      (let ((,newval ,value))
+        (handler-bind ((error
+                         (lambda (&rest ignore)
+                           (declare (ignore ignore))
+                           (invoke-restart 'cl:continue))))
+          (makunbound ',name))
+        (defconstant ,name ,newval ,@(when doc (list doc)))))))
 
 (defmacro class (name (&rest supers) &body slots-and-options)
   "Define a class.