Classification.Upper
val t :
[ `Branch
| `Control
| `Control_tmp
| `Dict
| `Gc_result of int
| `Mapping of int
| `Prefix of int
| `Reachable of int
| `Sorted of int
| `Suffix of int
| `Unknown
| `V1_or_v2_pack ]
Brassaia.Type.t
val init : string -> t