module BatInnerWeaktbl: sig .. end
Weak hash table library for OCaml, with an interface compatible with
the standard Hashtbl module.
Generic interface
type ('a, 'b) t
The type of hash tables from type 'a to type 'b.
val create : int -> ('a, 'b) t
Weaktbl.create n creates a new, empty hash table, with
initial size n. For best results, n should be on the
order of the expected number of elements that will be in
the table. The table grows as needed, so n is just an
initial guess.
val clear : ('a, 'b) t -> unit
Empty a hash table.
val add : ('a, 'b) t -> 'a -> 'b -> unit
Weaktbl.add tbl x y adds a binding of x to y in table tbl.
Previous bindings for x are not removed, but simply
hidden. That is, after performing Weaktbl.remove tbl x,
the previous binding for x, if any, is restored.
(Same behavior as with association lists.)
val copy : ('a, 'b) t -> ('a, 'b) t
Return a copy of the given hashtable.
val find : ('a, 'b) t -> 'a -> 'b
Weaktbl.find tbl x returns the current binding of x in tbl,
or raises Not_found if no such binding exists.
val find_all : ('a, 'b) t -> 'a -> 'b list
Weaktbl.find_all tbl x returns the list of all data
associated with x in tbl.
The current binding is returned first, then the previous
bindings, in reverse order of introduction in the table.
val mem : ('a, 'b) t -> 'a -> bool
Weaktbl.mem tbl x checks if x is bound in tbl.
val remove : ('a, 'b) t -> 'a -> unit
Weaktbl.remove tbl x removes the current binding of x in tbl,
restoring the previous binding if it exists.
It does nothing if x is not bound in tbl.
val replace : ('a, 'b) t -> 'a -> 'b -> unit
Weaktbl.replace tbl x y replaces the current binding of x
in tbl by a binding of x to y. If x is unbound in tbl,
a binding of x to y is added to tbl.
This is functionally equivalent to Weaktbl.remove tbl x
followed by Weaktbl.add tbl x y.
val iter : ('a -> 'b -> unit) -> ('a, 'b) t -> unit
Weaktbl.iter f tbl applies f to all bindings in table tbl.
f receives the key as first argument, and the associated value
as second argument. Each binding is presented exactly once to f.
The order in which the bindings are passed to f is unspecified.
However, if the table contains several bindings for the same key,
they are passed to f in reverse order of introduction, that is,
the most recent binding is passed first.
val fold : ('a -> 'b -> 'c -> 'c) -> ('a, 'b) t -> 'c -> 'c
Weaktbl.fold f tbl init computes
(f kN dN ... (f k1 d1 init)...),
where k1 ... kN are the keys of all bindings in tbl,
and d1 ... dN are the associated values.
Each binding is presented exactly once to f.
The order in which the bindings are passed to f is unspecified.
However, if the table contains several bindings for the same key,
they are passed to f in reverse order of introduction, that is,
the most recent binding is passed first.
val length : ('a, 'b) t -> int
Weaktbl.length tbl returns the number of bindings in tbl.
Multiple bindings are counted multiply, so Weaktbl.length
gives the number of times Weaktbl.iter calls its first argument.
Functorial interface
module Make: functor (H : Hashtbl.HashedType) -> Hashtbl.S with type key = H.t
Functor building an implementation of the hashtable structure.