diff --git a/lex.py b/lex.py
index 94f98da..45f3882 100755
--- a/lex.py
+++ b/lex.py
@@ -205,7 +205,7 @@ class LazyPatternRule(Rule):
     def __init__(self, name, pattern):
         Rule.__init__(self, name)
         self.pattern = pattern
-        self.d       = {}
+        self._compile({})
     def _compile(self, d):
         try:
             self.re = re.compile(self.pattern % d, self.reflags)