octez-libs 20.1 · OCaml Package

type t

The type for context views.

type key

The type for context keys.

type value

The type for context values.

type tree

The type for context trees.

Getters

val mem : t -> key -> bool Lwt.t

mem t k is an Lwt promise that resolves to true iff k is bound to a value in t.

val mem_tree : t -> key -> bool Lwt.t

mem_tree t k is like mem but for trees.

val find : t -> key -> value option Lwt.t

find t k is an Lwt promise that resolves to Some v if k is bound to the value v in t and None otherwise.

val find_tree : t -> key -> tree option Lwt.t

find_tree t k is like find but for trees.

val list : t -> ?offset:int -> ?length:int -> key -> (string * tree) list Lwt.t

list t key is the list of files and sub-nodes stored under k in t. The result order is not specified but is stable.

offset and length are used for pagination.

val length : t -> key -> int Lwt.t

length t key is an Lwt promise that resolves to the number of files and sub-nodes stored under k in t.

It is equivalent to let+ l = list t k in List.length l but has a constant-time complexity.

Setters

val add : t -> key -> value -> t Lwt.t

add t k v is an Lwt promise that resolves to c such that:

k is bound to v in c;
and c is similar to t otherwise.

If k was already bound in t to a value that is physically equal to v, the result of the function is a promise that resolves to t. Otherwise, the previous binding of k in t disappears.

val add_tree : t -> key -> tree -> t Lwt.t

add_tree is like add but for trees.

val remove : t -> key -> t Lwt.t

remove t k v is an Lwt promise that resolves to c such that:

k is unbound in c;
and c is similar to t otherwise.

Folding

val fold : 
  ?depth:depth ->
  t ->
  key ->
  order:[ `Sorted | `Undefined ] ->
  init:'a ->
  f:(key -> tree -> 'a -> 'a Lwt.t) ->
  'a Lwt.t

fold ?depth t root ~order ~init ~f recursively folds over the trees and values of t. The f callbacks are called with a key relative to root. f is never called with an empty key for values; i.e., folding over a value is a no-op.

The depth is 0-indexed. If depth is set (by default it is not), then f is only called when the conditions described by the parameter is true:

Eq d folds over nodes and values of depth exactly d.
Lt d folds over nodes and values of depth strictly less than d.
Le d folds over nodes and values of depth less than or equal to d.
Gt d folds over nodes and values of depth strictly more than d.
Ge d folds over nodes and values of depth more than or equal to d.

If order is `Sorted (the default), the elements are traversed in lexicographic order of their keys. For large nodes, it is memory-consuming, use `Undefined for a more memory efficient fold.

Configuration

val config : t -> Config.t

config t is t's hash configuration.

package octez-libs

Getters

Setters

Folding

Configuration