Thu Jan 21 01:56:47 UTC 2010  pix@kepibu.org
  * Rather than a new UNIFY** function, make UNIFY* work that way
  Let errors which are not UNIFICATION-FAILUREs find their way out of UNIFY*.
diff -rN -u old-cl-unification-1/match-block.lisp new-cl-unification-1/match-block.lisp
--- old-cl-unification-1/match-block.lisp	2013-07-26 01:08:55.000000000 +0000
+++ new-cl-unification-1/match-block.lisp	2013-07-26 01:08:55.000000000 +0000
@@ -167,7 +167,7 @@
              (let ((template (%template-for-match template))
                    )
                `((setf ,clause-var
-                       (unify** ,template ,object ,substitution))
+                       (unify* ,template ,object ,substitution))
                  ,(%wrap-var-bindings template clause-var forms))
                ))
 
diff -rN -u old-cl-unification-1/unifier.lisp new-cl-unification-1/unifier.lisp
--- old-cl-unification-1/unifier.lisp	2013-07-26 01:08:55.000000000 +0000
+++ new-cl-unification-1/unifier.lisp	2013-07-26 01:08:55.000000000 +0000
@@ -857,9 +857,6 @@
 ;;; Utilities.
 
 (defun unify* (a b &optional (env (make-empty-environment)))
-  (ignore-errors (unify a b env)))
-
-(defun unify** (a b &optional (env (make-empty-environment)))
   (handler-case
       (unify a b env)
     (unification-failure (c) (values nil c))))