Unary rules are broken in some cases

[redpony]

The parser does not always apply unary rules in the right order (in particular, when rules are loaded from multiple grammars). This can cause parse failures and missing derivations.

Example: foo

foo.scfg: [Y] ||| foo ||| foo ||| F=1 [X] ||| [Y] ||| [1] ||| F=1

Will fail, where as foo.scfg: [X] ||| foo ||| foo ||| F=1

will succeed.