diff --git a/pytools/lex.py b/pytools/lex.py
index 24dc62769fcc90bad3d3bc83dd37923d3b115175..a47ea459543c8e133fc5cfcf580820dc2be2d6d5 100644
--- a/pytools/lex.py
+++ b/pytools/lex.py
@@ -19,7 +19,7 @@ class InvalidTokenError:
                (self.index, self.string[self.index:self.index+20])
 
 
-class ParseError:
+class ParseError(RuntimeError):
     def __init__(self, msg, s, token):
         self.message = msg
         self.string = s