Check_closed.Mmodule Value : Type.SRead-only stores are store where it is only possible to read existing values.
type value = Value.tThe type for raw values.
val mem : [> Perms.read ] t -> key -> bool Lwt.tmem t k is true iff k is present in t.
val find : [> Perms.read ] t -> key -> value option Lwt.tfind t k is Some v if k is associated to v in t and None is k is not present in t.
val close : 'a t -> unit Lwt.tclose t frees up all the resources associated with t. Any operations run on a closed handle will raise Closed.
type hash = Hash.tThe type of hashes of value.
val add : [> Perms.write ] t -> value -> key Lwt.tWrite the contents of a value to the store, and obtain its key.
val unsafe_add : [> Perms.write ] t -> hash -> value -> key Lwt.tSame as add but allows specifying the value's hash directly. The backend might choose to discard that hash and/or can be corrupt if the hash is not consistent.
val index : [> Perms.read ] t -> hash -> key option Lwt.tIndexing maps the hash of a value to a corresponding key of that value in the store. For stores that are addressed by hashes directly, this is typically fun _t h -> Lwt.return (Key.of_hash h); for stores with more complex addressing schemes, index may attempt a lookup operation in the store.
In general, indexing is best-effort and reveals no information about the membership of the value in the store. In particular:
index t hash = Some key doesn't guarantee mem t key: the value with hash hash may still be absent from the store;index t hash = None doesn't guarantee that there is no key such that mem t key and Key.to_hash key = hash: the value may still be present in the store under a key that is not indexed.val batch :
Perms.read t ->
([ Perms.read | Perms.write ] t -> 'a Lwt.t) ->
'a Lwt.tbatch t f applies the writes in f in a separate batch. The exact guarantees depend on the implementation.
val v : Irmin__.Conf.t -> Perms.read t Lwt.tv config is a function returning fresh store handles, with the configuration config, which is provided by the backend.