Module type Ephemeron.S

The output signature of the functors K1.Make and K2.Make. These hash tables are weak in the keys. If all the keys of a binding are alive the binding is kept, but if one of the keys of the binding is dead then the binding is removed.

Propose the same interface as usual hash table. However since the bindings are weak, even if mem h k is true, a subsequent find h k may raise Not_found because the garbage collector can run between the two.

type key
type !'a t
val create : int -> 'a t
val clear : 'a t -> unit
val reset : 'a t -> unit
val copy : 'a t -> 'a t
val add : 'a t -> key -> 'a -> unit
val remove : 'a t -> key -> unit
val find : 'a t -> key -> 'a
val find_opt : 'a t -> key -> 'a option
val find_all : 'a t -> key -> 'a list
val replace : 'a t -> key -> 'a -> unit
val mem : 'a t -> key -> bool
val length : 'a t -> int
val stats : 'a t -> Hashtbl.statistics
val add_seq : 'a t -> (key * 'a) Seq.t -> unit
val replace_seq : 'a t -> (key * 'a) Seq.t -> unit
val of_seq : (key * 'a) Seq.t -> 'a t
val clean : 'a t -> unit

remove all dead bindings. Done automatically during automatic resizing.

val stats_alive : 'a t -> Hashtbl.statistics

same as Hashtbl.SeededS.stats but only count the alive bindings