Module Generic_key.Hash

Object hashes.

Signature for digest hashes, inspired by Digestif.

type t = hash

The type for digest hashes.

val hash : ((string -> unit) -> unit) -> t

Compute a deterministic store key from a sequence of strings.

val short_hash : t -> int

short_hash h is a small hash of h, to be used for instance as the `hash` function of an OCaml Hashtbl.

val hash_size : int

hash_size is the size of hash results, in bytes.

val to_raw_string : t -> string

to_raw_string t is the raw sequence of bytes in t (of length hash_size).

val unsafe_of_raw_string : string -> t

unsafe_of_raw_string b is the hash consisting of the raw sequence of bytes b.

Warning: this function cannot guarantee that the supplied byte string is a valid output of the hash process, so should only be used on strings that are known to have been built with to_raw_string.

val short_hash_substring : Bigstringaf.t -> off:int -> int

short_hash_substring t off computes the short-hash of the raw hash data contained in t at offset off. It has behaviour equivalent to:

Bigstringaf.substring t ~off ~len:hash_size
|> unsafe_of_raw_string
|> short_hash

but may be more efficient due to not needing to allocate an intermediate string.

Value Types

val t : t Irmin.Type.t

t is the value type for t.