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(*
* Copyright (c) Facebook, Inc. and its affiliates.
*
* This source code is licensed under the MIT license found in the
* LICENSE file in the root directory of this source tree.
*)
(** Qset - Set with (signed) rational multiplicity for each element *)
open Base
type ('elt, 'cmp) t = ('elt, Q.t, 'cmp) Map.t
module M (Elt : sig
type t
type comparator_witness
end) =
struct
type nonrec t = (Elt.t, Elt.comparator_witness) t
end
module type Sexp_of_m = sig
type t [@@deriving sexp_of]
end
module type M_of_sexp = sig
type t [@@deriving of_sexp]
include Comparator.S with type t := t
end
module type Compare_m = sig end
module type Hash_fold_m = Hasher.S
let sexp_of_q q = Sexp.Atom (Q.to_string q)
let q_of_sexp = function Sexp.Atom s -> Q.of_string s | _ -> assert false
let hash_fold_q state q = Hash.fold_int state (Hashtbl.hash q)
let sexp_of_m__t (type elt) (module Elt : Sexp_of_m with type t = elt) t =
Map.sexp_of_m__t (module Elt) sexp_of_q t
let m__t_of_sexp (type elt cmp)
(module Elt : M_of_sexp
with type t = elt
and type comparator_witness = cmp) sexp =
Map.m__t_of_sexp (module Elt) q_of_sexp sexp
let compare_m__t (module Elt : Compare_m) = Map.compare_direct Q.compare
let equal_m__t (module Elt : Compare_m) = Map.equal Q.equal
let hash_fold_m__t (type elt) (module Elt : Hash_fold_m with type t = elt)
state =
Map.hash_fold_m__t (module Elt) hash_fold_q state
let hash_m__t (type elt) (module Elt : Hash_fold_m with type t = elt) =
Hash.of_fold (hash_fold_m__t (module Elt))
type ('elt, 'cmp) comparator =
(module Comparator.S with type t = 'elt and type comparator_witness = 'cmp)
let empty cmp = Map.empty cmp
let if_nz q = if Q.equal Q.zero q then None else Some q
let add m x i =
Map.change m x ~f:(function Some j -> if_nz Q.(i + j) | None -> if_nz i)
let remove m x = Map.remove m x
let union m n =
Map.merge m n ~f:(fun ~key:_ -> function
| `Both (i, j) -> if_nz Q.(i + j) | `Left i | `Right i -> Some i )
let length m = Map.length m
let count m x = match Map.find m x with Some q -> q | None -> Q.zero
let count_and_remove m x =
let found = ref Q.zero in
let m =
Map.change m x ~f:(function
| None -> None
| Some i ->
found := i ;
None )
in
if Q.equal !found Q.zero then None else Some (!found, m)
let min_elt = Map.min_elt
let min_elt_exn = Map.min_elt_exn
let fold m ~f ~init = Map.fold m ~f:(fun ~key ~data s -> f key data s) ~init
let map m ~f =
let m' = Map.empty (Map.comparator_s m) in
let m, m' =
fold m ~init:(m, m') ~f:(fun x i (m, m') ->
let x', i' = f x i in
if phys_equal x' x then
if Q.equal i' i then (m, m') else (Map.set m ~key:x ~data:i', m')
else (Map.remove m x, add m' x' i') )
in
fold m' ~init:m ~f:(fun x i m -> add m x i)
let fold_map m ~f ~init:s =
let m' = Map.empty (Map.comparator_s m) in
let m, m', s =
fold m ~init:(m, m', s) ~f:(fun x i (m, m', s) ->
let x', i', s = f x i s in
if phys_equal x' x then
if Q.equal i' i then (m, m', s)
else (Map.set m ~key:x ~data:i', m', s)
else (Map.remove m x, add m' x' i', s) )
in
(fold m' ~init:m ~f:(fun x i m -> add m x i), s)
let for_all m ~f = Map.for_alli m ~f:(fun ~key ~data -> f key data)
let map_counts m ~f = Map.mapi m ~f:(fun ~key ~data -> f key data)
let iter m ~f = Map.iteri m ~f:(fun ~key ~data -> f key data)
let exists m ~f = Map.existsi m ~f:(fun ~key ~data -> f key data)
let to_list m = Map.to_alist m