Addition to docs -- `ParseError` new attributes.
@@ -20,6 +20,12 @@ be performed it will report an error by raising an instance of
parser it will always be a single element list. In the case of GLR there might
be more symbols if there were multiple parser heads.
+- **last_heads (list)** - A list of last GLR parser heads. Available only for
+ GLR parsing.
+
+- **grammar (Grammar)** - An instance of `parglare.Grammar` class used for
+ parsing.
+
# Error recovery
