1 files changed, 3 insertions, 0 deletions
diff --git a/Parsers.hs b/Parsers.hs
index 84b4856..a7f70a2 100644
--- a/Parsers.hs
+++ b/Parsers.hs
@@ -39,6 +39,9 @@ instance Alternative (Parser t) where
 
 instance MonadPlus (Parser t)
 
+instance MonadFail (Parser t) where
+  fail _ = mzero
+
 -----------------------------------------------------------------------------
 
 flunk :: Parser t a