This sub-module contains the extension of the standard polymorphic Hashtbl.
module Poly : sig ... endinclude module type of Polyval get_or : ('a, 'b) Hashtbl.t ‑> 'a ‑> default:'b ‑> 'bget_or tbl k ~default returns the value associated to k if present,
and returns default otherwise (if k doesn't belong in tbl).
val keys_list : ('a, 'b) Hashtbl.t ‑> 'a listkeys_list t is the list of keys in t.
If the key is in the Hashtable multiple times, all occurrences will be returned.
val map_list : ('a ‑> 'b ‑> 'c) ‑> ('a, 'b) Hashtbl.t ‑> 'c listMap on a hashtable's items, collect into a list.
val incr : ?by:int ‑> ('a, int) Hashtbl.t ‑> 'a ‑> unitincr ?by tbl x increments or initializes the counter associated with x.
If get tbl x = None, then after update, get tbl x = Some 1;
otherwise, if get tbl x = Some n, now get tbl x = Some (n+1).
by rather than 1.val decr : ?by:int ‑> ('a, int) Hashtbl.t ‑> 'a ‑> unitLike incr but subtract 1 (or the value of by).
If the value reaches 0, the key is removed from the table.
This does nothing if the key is not already present in the table.
val add_list : ('a, 'b list) Hashtbl.t ‑> 'a ‑> 'b ‑> unitadd_list tbl x y adds y to the list x is bound to. If x is
not bound, it becomes bound to y.
val add_seq : ('a, 'b) Hashtbl.t ‑> ('a * 'b) sequence ‑> unitAdd the corresponding pairs to the table, using Hashtbl.add.
val add_seq_count : ('a, int) Hashtbl.t ‑> 'a sequence ‑> unitadd_seq_count tbl seq increments the count of each element of seq
by calling incr. This is useful for counting how many times each
element of seq occurs.
val of_seq_count : 'a sequence ‑> ('a, int) Hashtbl.tLike add_seq_count, but allocates a new table and returns it.
val of_list : ('a * 'b) list ‑> ('a, 'b) Hashtbl.tBuild a table from the given list of bindings k_i -> v_i,
added in order using add. If a key occurs several times,
it will be added several times, and the visible binding
will be the last one.
val update : ('a, 'b) Hashtbl.t ‑> f:('a ‑> 'b option ‑> 'b option) ‑> k:'a ‑> unitupdate tbl ~f ~k updates key k by calling f k (Some v) if
k was mapped to v, or f k None otherwise; if the call
returns None then k is removed/stays removed, if the call
returns Some v' then the binding k -> v' is inserted
using Hashtbl.replace.
module type S : sig ... end