File: pMap.ml

package info (click to toggle)
sks 1.1.6-14
  • links: PTS, VCS
  • area: main
  • in suites: bullseye, buster, sid
  • size: 2,296 kB
  • sloc: ml: 15,228; ansic: 1,069; sh: 358; makefile: 347
file content (172 lines) | stat: -rw-r--r-- 6,115 bytes parent folder | download | duplicates (5)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
(***********************************************************************)
(* pMap.ml - Association tables over ordered types.                    *)
(*                                                                     *)
(* Copyright (C) 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010, *)
(*               2011, 2012, 2013  Yaron Minsky and Contributors       *)
(*                                                                     *)
(* This file is part of SKS.  SKS is free software; you can            *)
(* redistribute it and/or modify it under the terms of the GNU General *)
(* Public License as published by the Free Software Foundation; either *)
(* version 2 of the License, or (at your option) any later version.    *)
(*                                                                     *)
(* This program is distributed in the hope that it will be useful, but *)
(* WITHOUT ANY WARRANTY; without even the implied warranty of          *)
(* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU   *)
(* General Public License for more details.                            *)
(*                                                                     *)
(* You should have received a copy of the GNU General Public License   *)
(* along with this program; if not, write to the Free Software         *)
(* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 *)
(* USA or see <http://www.gnu.org/licenses/>.                          *)
(***********************************************************************)

open StdLabels
open MoreLabels


module type OrderedType =
  sig val compare: 'a -> 'a -> int end

module ClassicalType =
  struct let compare = Pervasives.compare end

module type S =
  sig
    type ('key,'data) t
    val empty: ('key,'data) t
    val add: key:'key -> data:'data -> ('key,'data) t -> ('key,'data) t
    val find: 'key -> ('key,'data) t -> 'data
    val remove: 'key -> ('key,'data) t -> ('key,'data) t
    val mem:  'key -> ('key,'data) t -> bool
    val iter: f:(key:'key -> data:'data -> unit) -> ('key,'data) t -> unit
    val map: f:('data -> 'a) -> ('key,'data) t -> ('key,'a) t
    val mapi: f:(key:'key -> data:'data -> 'a) ->
      ('key,'data) t -> ('key,'a) t
    val fold: f:(key:'key -> data:'data -> 'a -> 'a) ->
      ('key,'data) t -> init:'a -> 'a
    val of_alist: ('key * 'data) list -> ('key,'data) t
    val to_alist: ('key,'data) t -> ('key * 'data) list
  end

module Make(Ord: OrderedType) = struct

    type ('key,'data) t =
        Empty
      | Node of ('key,'data) t * 'key * 'data * ('key,'data) t * int

    let empty = Empty

    let height = function
        Empty -> 0
      | Node(_,_,_,_,h) -> h

    let create l x d r =
      let hl = height l and hr = height r in
      Node(l, x, d, r, (if hl >= hr then hl + 1 else hr + 1))

    let bal l x d r =
      let hl = match l with Empty -> 0 | Node(_,_,_,_,h) -> h in
      let hr = match r with Empty -> 0 | Node(_,_,_,_,h) -> h in
      if hl > hr + 2 then begin
        match l with
          Empty -> invalid_arg "Map.bal"
        | Node(ll, lv, ld, lr, _) ->
            if height ll >= height lr then
              create ll lv ld (create lr x d r)
            else begin
              match lr with
                Empty -> invalid_arg "Map.bal"
              | Node(lrl, lrv, lrd, lrr, _)->
                  create (create ll lv ld lrl) lrv lrd (create lrr x d r)
            end
      end else if hr > hl + 2 then begin
        match r with
          Empty -> invalid_arg "Map.bal"
        | Node(rl, rv, rd, rr, _) ->
            if height rr >= height rl then
              create (create l x d rl) rv rd rr
            else begin
              match rl with
                Empty -> invalid_arg "Map.bal"
              | Node(rll, rlv, rld, rlr, _) ->
                  create (create l x d rll) rlv rld (create rlr rv rd rr)
            end
      end else
        Node(l, x, d, r, (if hl >= hr then hl + 1 else hr + 1))

    let rec add ~key:x ~data = function
        Empty ->
          Node(Empty, x, data, Empty, 1)
      | Node(l, v, d, r, h) ->
          let c = Ord.compare x v in
          if c = 0 then
            Node(l, x, data, r, h)
          else if c < 0 then
            bal (add ~key:x ~data l) v d r
          else
            bal l v d (add ~key:x ~data r)

    let rec find x = function
        Empty ->
          raise Not_found
      | Node(l, v, d, r, _) ->
          let c = Ord.compare x v in
          if c = 0 then d
          else find x (if c < 0 then l else r)

    let rec mem x = function
        Empty ->
          false
      | Node(l, v, d, r, _) ->
          let c = Ord.compare x v in
          c = 0 || mem x (if c < 0 then l else r)

    let rec merge t1 t2 =
      match (t1, t2) with
        (Empty, t) -> t
      | (t, Empty) -> t
      | (Node(l1, v1, d1, r1, h1), Node(l2, v2, d2, r2, h2)) ->
          bal l1 v1 d1 (bal (merge r1 l2) v2 d2 r2)

    let rec remove x = function
        Empty ->
          Empty
      | Node(l, v, d, r, h) ->
          let c = Ord.compare x v in
          if c = 0 then
            merge l r
          else if c < 0 then
            bal (remove x l) v d r
          else
            bal l v d (remove x r)

    let rec iter ~f = function
        Empty -> ()
      | Node(l, v, d, r, _) ->
          iter ~f l; f ~key:v ~data:d; iter ~f r

    let rec map ~f = function
        Empty               -> Empty
      | Node(l, v, d, r, h) -> Node(map ~f l, v, f d, map ~f r, h)

    let rec mapi ~f = function
        Empty               -> Empty
      | Node(l, v, d, r, h) ->
          Node(mapi ~f l, v, f ~key:v ~data:d, mapi ~f r, h)

    let rec fold ~f m ~init:accu =
      match m with
        Empty -> accu
      | Node(l, v, d, r, _) ->
          fold ~f l ~init:(f ~key:v ~data:d (fold ~f r ~init:accu))

    let of_alist alist =
      List.fold_left ~f:(fun map (key,data) -> add ~key ~data map)
        ~init:empty alist

    let to_alist map =
      fold ~f:(fun ~key ~data list -> (key,data)::list)
        ~init:[] map
end

module Map = Make(ClassicalType)