Add exceptions :) implement catch/3 and throw/1

1 files changed, 1 insertions, 0 deletions

diff --git a/dat.h b/dat.h
index 2cf28b7..ce6a0df 100644
--- a/dat.h
+++ b/dat.h
@@ -29,6 +29,7 @@ struct Binding
 struct Goal
 {
 	Term *goal;
+	Term *catcher; /* When this is non-nil, the goal is a catch frame, goal is the recovery. */
 	Goal *next;
 };