-rewrite ::= sequence /ws => "rewrite"
- | sequence ^"=>" word /ws
- | sequence ^"=>" quoted /ws
- | sequence "=>" "()" /ws => "wrap"
+NonTerminal = Word "=" RHS /ws
+ | Word "*" ws! ^"=" ws! RHS
+ | Word "*/" Word ws! ^"=" ws! RHS
+
+RHS = (Sequence +/ (ws! "|" ws!)) +/ (ws! ">" ws!)