1 files changed, 5 insertions, 4 deletions
diff --git a/gtwiwtg.lisp b/gtwiwtg.lisp
index 14c0048..10eb1ab 100644
--- a/gtwiwtg.lisp
+++ b/gtwiwtg.lisp
@@ -779,10 +779,11 @@ A -- 4
                        `(let ((,var-exp (next ,gen-var))) ,@body))))
     `(let ((,gen-var ,gen))
        (assert (typep ,gen-var 'gtwiwtg::generator!))
-       (loop
-          :while (has-next-p ,gen-var)
-          :do
-            ,expr-body)
+       (unwind-protect 
+            (loop
+               :while (has-next-p ,gen-var)
+               :do
+                 ,expr-body))
        (stop ,gen-var))))
 
 (defmacro fold ((acc init-val) (var-exp gen) expr)