Mon Nov 23 13:19:59 UTC 2009  pix@kepibu.org
  * Fail unification if no match for a selector
diff -rN -u old-Oh, Ducks!/notes new-Oh, Ducks!/notes
--- old-Oh, Ducks!/notes	2013-08-10 17:39:27.000000000 +0000
+++ new-Oh, Ducks!/notes	2013-08-10 17:39:27.000000000 +0000
@@ -109,8 +109,6 @@
 
 I also recommend submitting a patch.  Other people might want to use
 that selector, too!
-* Known Bugs
-** Failure to match results in NIL, rather than a unification-failure
 * To Do
 ** working lhtml/xmls support [1/2]
  * [X] non-descendant cases (class, id, etc.)
diff -rN -u old-Oh, Ducks!/tests.lisp new-Oh, Ducks!/tests.lisp
--- old-Oh, Ducks!/tests.lisp	2013-08-10 17:39:27.000000000 +0000
+++ new-Oh, Ducks!/tests.lisp	2013-08-10 17:39:27.000000000 +0000
@@ -53,7 +53,7 @@
           "<div>I do <i>not</i> <i>like</i> cheese.</div><div><span>I like <i>cheese</i>.</span></div>")
   (values div i))
 
-#+FIXME ;; should throw 'unification-failure
+;; throws 'unification-failure
 (match (#T(html (:model dom)
                 ("q" . ?div))
           "<div>I do <i>not</i> <i>like</i> cheese.</div><div><span>I like <i>cheese</i>.</span></div>")
diff -rN -u old-Oh, Ducks!/unify.lisp new-Oh, Ducks!/unify.lisp
--- old-Oh, Ducks!/unify.lisp	2013-08-10 17:39:27.000000000 +0000
+++ new-Oh, Ducks!/unify.lisp	2013-08-10 17:39:27.000000000 +0000
@@ -20,6 +20,10 @@
               (t
                (let ((val (find-matching-elements css-specifier document)))
                  (cond
+                   ((null val)
+                    (error 'unification-failure
+                           :format-control "Unable to unify ~s and ~s"
+                           :format-arguments (list css-specifier template)))
                    ((unify::template-p template)
                     (unify template val env))
                    ((unify::variablep template)