module Make:
Functor building an implementation of the weak hash table structure.
type data
The type of the elements stored in the table.
type t
The type of tables that contain elements of type
data.
Note that weak hash tables cannot be marshaled using
output_value or the functions of the
Marshal
module.
val create : int -> t
create n creates a new empty weak hash table, of initial
size n. The table will grow as needed.
val clear : t -> unit
Remove all elements from the table.
val merge : t -> data -> data
merge t x returns an instance of x found in t if any,
or else adds x to t and return x.
val add : t -> data -> unit
add t x adds x to t. If there is already an instance
of x in t, it is unspecified which one will be
returned by subsequent calls to find and merge.
val remove : t -> data -> unit
remove t x removes from t one instance of x. Does
nothing if there is no instance of x in t.
val find : t -> data -> data
find t x returns an instance of x found in t.
Raise Not_found if there is no such element.
val find_all : t -> data -> data list
find_all t x returns a list of all the instances of x
found in t.
val mem : t -> data -> bool
mem t x returns true if there is at least one instance
of x in t, false otherwise.
val iter : (data -> unit) -> t -> unit
iter f t calls f on each element of t, in some unspecified
order. It is not specified what happens if f tries to change
t itself.
val fold : (data -> 'a -> 'a) -> t -> 'a -> 'a
fold f t init computes (f d1 (... (f dN init))) where
d1 ... dN are the elements of t in some unspecified order.
It is not specified what happens if f tries to change t
itself.
val count : t -> int
Count the number of elements in the table. count t gives the
same result as fold (fun _ n -> n+1) t 0 but does not delay the
deallocation of the dead elements.
val stats : t -> int * int * int * int * int * int
Return statistics on the table. The numbers are, in order:
table length, number of entries, sum of bucket lengths,
smallest bucket length, median bucket length, biggest bucket length.