040000 tree 54abf26a6f4cd1cdf9fc14af09e671174d0ab1f4	exceptions
040000 tree d7b92a931f194f906ced3956754067c9dda4a455	protocol
040000 tree c05f9235059b938e9ae369b368d08262db92819e	types
040000 tree b0772ea7491169e2f0a1dc2dddba6170c3363db4	util