CCHashTrie.TransientIdentifiers for transient modifications. A transient modification is uniquely identified by a Transient.t. Once Transient.freeze r is called, r cannot be used to modify the structure again.
val create : unit -> tCreate a new, active ID.
val frozen : t -> boolfrozen i returns true if freeze i was called before. In this case, the ID cannot be used for modifications again.
val active : t -> boolactive i is not (frozen i).
val freeze : t -> unitfreeze i makes i unusable for new modifications. The values created with i will now be immutable.
val with_ : (t -> 'a) -> 'awith_ f creates a transient ID i, calls f i, freezes the ID i and returns the result of f i.