mdw-base.lisp: Make locative slots be read-only.

diff --git a/mdw-base.lisp b/mdw-base.lisp
index b9e9257..6cdcccf 100644 (file)
--- a/mdw-base.lisp
+++ b/mdw-base.lisp
@@ -412,8 +412,8 @@
 (export 'locp)
 (defstruct (loc (:predicate locp) (:constructor make-loc (reader writer)))
   "Locative data type.  See `locf' and `ref'."
-  (reader (slot-uninitialized) :type function)
-  (writer (slot-uninitialized) :type function))
+  (reader (slot-uninitialized) :type function :read-only t)
+  (writer (slot-uninitialized) :type function :read-only t))
 
 (export 'locf)
 (defmacro locf (place &environment env)