Rules with a rule as first subrule cause SystemStackError error

[callahat]

@grammar_with_self_referential_rule.add_rules :S,
    [ [@terminal_a, :S, @terminal_a], [] ],
    [ [@terminal_a], [] ] ,
    [ [:S, @repetition], []  ]

This will cause a SystemStackError when match? or translate is ran, since the last subrule will keep attempting to see if :S matches. There is a test that validates the exception is thrown which could be changed to check that this is still broken or has been fixed.