040000 tree facce71fd05a5ffb3d7525471cfbc7805cd81b95	exceptions
040000 tree 25d5e405f33856e0eb09e97d374260935ec33c40	protocol
040000 tree 742f66142f972cfe921b4d491215027be47678bf	types
040000 tree cd4cde648d52058b3463c49dfc7d933749bb717c	util