Added check for unused rules in grammar.

bl0b · Dec 27, 2011 · db2fab3 · db2fab3
1 parent 5dd5ecc
commit db2fab3
Showing 1 changed file with 6 additions and 0 deletions.
diff --git a/jupyLR/parser.py b/jupyLR/parser.py
@@ -212,3 +212,9 @@ def dump_sets(self):
         for i, lrset in enumerate(self.LR0):
             print self.itemsetstr(lrset, i)
             print
+
+    @property
+    def unused_rules(self):
+        unused = lambda i: reduce(lambda a, b: a and i not in b, a.LR0, True)
+        unused_rule_indices = set(x[0] for x in filter(check, a.I))
+        return set(a.R[x][0] for x in unused_rule_indices)