condition: add print-stack-trace, fix handling of nil forms in handler-case

2 files changed, 16 insertions, 2 deletions

diff --git a/src/clojure/contrib/condition.clj b/src/clojure/contrib/condition.clj
index c396a7a9..c9ffb908 100644
--- a/src/clojure/contrib/condition.clj
+++ b/src/clojure/contrib/condition.clj
@@ -77,9 +77,9 @@ http://groups.google.com/group/clojure/browse_frm/thread/da1285c538f22bb5"}
   handled and *selector* is bound to to the value returned by dispatch-fn
   that matched the handler's key."
   [dispatch-fn & body]
-  (loop [[form & forms] body
+  (loop [[form & forms :as body] body
          m {:code [] :handlers []}]
-    (if form
+    (if (seq body)
       (recur
        forms
        (if (and (list? form) (= (first form) 'handle))
@@ -96,3 +96,14 @@ http://groups.google.com/group/clojure/browse_frm/thread/da1285c538f22bb5"}
             (cond
              ~@(:handlers m)
              :else (raise))))))))
+
+(defn print-stack-trace
+  "Prints the stack trace for a condition"
+  [condition]
+  (printf "condition\n")
+  (doseq [frame (:stack-trace condition)]
+    (printf "        at %s.%s(%s:%s)\n"
+            (.getClassName frame)
+            (.getMethodName frame)
+            (.getFileName frame)
+            (.getLineNumber frame))))
diff --git a/src/clojure/contrib/condition/example.clj b/src/clojure/contrib/condition/example.clj
index e437cf6e..04ef7d67 100644
--- a/src/clojure/contrib/condition/example.clj
+++ b/src/clojure/contrib/condition/example.clj
@@ -34,6 +34,8 @@
 
   (handler-case :source
     (handler-case :source
+      nil
+      nil
       (println (func 8 2))
       (println (func -6 17))
       ;; no handler for ::Args
@@ -42,4 +44,5 @@
     (println (func 3 4))
     (println (func -5 10))
     (handle ::Args
+      (print-stack-trace *condition*)
       (printf "Bad argument: %s\n" *condition*))))