Source file lwt_seq.ml
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
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
open Lwt.Syntax
open Lwt.Infix
type +'a node = Nil | Cons of 'a * 'a t
and 'a t = unit -> 'a node Lwt.t
let return_nil = Lwt.return Nil
let empty : 'a t = fun () -> return_nil
let return (x : 'a) : 'a t = fun () -> Lwt.return (Cons (x, empty))
let return_lwt (x : 'a Lwt.t) : 'a t = fun () ->
let+ x = x in
Cons (x, empty)
let cons x t () = Lwt.return (Cons (x, t))
let cons_lwt x t () =
let+ x = x in
Cons (x, t)
let rec append seq1 seq2 () =
seq1 () >>= function
| Nil -> seq2 ()
| Cons (x, next) -> Lwt.return (Cons (x, append next seq2))
let append seq1 seq2 () =
Lwt.apply seq1 () >>= function
| Nil -> seq2 ()
| Cons (x, next) -> Lwt.return (Cons (x, append next seq2))
let rec map f seq () =
seq () >|= function
| Nil -> Nil
| Cons (x, next) ->
let x = f x in
Cons (x, map f next)
let map f seq () =
Lwt.apply seq () >|= function
| Nil -> Nil
| Cons (x, next) ->
let x = f x in
Cons (x, map f next)
let rec map_s f seq () =
seq () >>= function
| Nil -> return_nil
| Cons (x, next) ->
let+ x = f x in
Cons (x, map_s f next)
let map_s f seq () =
Lwt.apply seq () >>= function
| Nil -> return_nil
| Cons (x, next) ->
let+ x = f x in
Cons (x, map_s f next)
let rec filter_map f seq () =
seq () >>= function
| Nil -> return_nil
| Cons (x, next) -> (
let x = f x in
match x with
| None -> filter_map f next ()
| Some y -> Lwt.return (Cons (y, filter_map f next) ))
let filter_map f seq () =
Lwt.apply seq () >>= function
| Nil -> return_nil
| Cons (x, next) -> (
let x = f x in
match x with
| None -> filter_map f next ()
| Some y -> Lwt.return (Cons (y, filter_map f next) ))
let rec filter_map_s f seq () =
seq () >>= function
| Nil -> return_nil
| Cons (x, next) -> (
let* x = f x in
match x with
| None -> filter_map_s f next ()
| Some y -> Lwt.return (Cons (y, filter_map_s f next) ))
let filter_map_s f seq () =
Lwt.apply seq () >>= function
| Nil -> return_nil
| Cons (x, next) -> (
let* x = f x in
match x with
| None -> filter_map_s f next ()
| Some y -> Lwt.return (Cons (y, filter_map_s f next) ))
let rec filter f seq () =
seq () >>= function
| Nil -> return_nil
| Cons (x, next) ->
let ok = f x in
if ok then Lwt.return (Cons (x, filter f next)) else filter f next ()
let filter f seq () =
Lwt.apply seq () >>= function
| Nil -> return_nil
| Cons (x, next) ->
let ok = f x in
if ok then Lwt.return (Cons (x, filter f next)) else filter f next ()
let rec filter_s f seq () =
seq () >>= function
| Nil -> return_nil
| Cons (x, next) ->
let* ok = f x in
if ok then Lwt.return (Cons (x, filter_s f next)) else filter_s f next ()
let filter_s f seq () =
Lwt.apply seq () >>= function
| Nil -> return_nil
| Cons (x, next) ->
let* ok = f x in
if ok then Lwt.return (Cons (x, filter_s f next)) else filter_s f next ()
let rec flat_map f seq () =
seq () >>= function
| Nil -> return_nil
| Cons (x, next) ->
flat_map_app f (f x) next ()
and flat_map_app f seq tail () =
seq () >>= function
| Nil -> flat_map f tail ()
| Cons (x, next) -> Lwt.return (Cons (x, flat_map_app f next tail))
let flat_map f seq () =
Lwt.apply seq () >>= function
| Nil -> return_nil
| Cons (x, next) ->
flat_map_app f (f x) next ()
let fold_left f acc seq =
let rec aux f acc seq =
seq () >>= function
| Nil -> Lwt.return acc
| Cons (x, next) ->
let acc = f acc x in
aux f acc next
in
let aux f acc seq =
Lwt.apply seq () >>= function
| Nil -> Lwt.return acc
| Cons (x, next) ->
let acc = f acc x in
aux f acc next
in
aux f acc seq
let fold_left_s f acc seq =
let rec aux f acc seq =
seq () >>= function
| Nil -> Lwt.return acc
| Cons (x, next) ->
let* acc = f acc x in
aux f acc next
in
let aux f acc seq =
Lwt.apply seq () >>= function
| Nil -> Lwt.return acc
| Cons (x, next) ->
let* acc = f acc x in
aux f acc next
in
aux f acc seq
let iter f seq =
let rec aux seq =
seq () >>= function
| Nil -> Lwt.return_unit
| Cons (x, next) ->
f x;
aux next
in
let aux seq =
Lwt.apply seq () >>= function
| Nil -> Lwt.return_unit
| Cons (x, next) ->
f x;
aux next
in
aux seq
let iter_s f seq =
let rec aux seq =
seq () >>= function
| Nil -> Lwt.return_unit
| Cons (x, next) ->
let* () = f x in
aux next
in
let aux seq =
Lwt.apply seq () >>= function
| Nil -> Lwt.return_unit
| Cons (x, next) ->
let* () = f x in
aux next
in
aux seq
let iter_p f seq =
let rec aux acc seq =
seq () >>= function
| Nil -> Lwt.join acc
| Cons (x, next) ->
let p = f x in
aux (p::acc) next
in
let aux acc seq =
Lwt.apply seq () >>= function
| Nil -> Lwt.join acc
| Cons (x, next) ->
let p = f x in
aux (p::acc) next
in
aux [] seq
let iter_n ?(max_concurrency = 1) f seq =
begin
if max_concurrency <= 0 then
let message =
Printf.sprintf
"Lwt_seq.iter_n: max_concurrency must be > 0, %d given"
max_concurrency
in
invalid_arg message
end;
let rec loop running available seq =
begin
if available > 0 then (
Lwt.return (running, available)
)
else (
Lwt.nchoose_split running >>= fun (complete, running) ->
Lwt.return (running, available + List.length complete)
)
end >>= fun (running, available) ->
seq () >>= function
| Nil ->
Lwt.join running
| Cons (elt, seq) ->
loop (f elt :: running) (pred available) seq
in
loop [] max_concurrency (fun () -> Lwt.apply seq ())
let rec unfold f u () =
match f u with
| None -> return_nil
| Some (x, u') -> Lwt.return (Cons (x, unfold f u'))
| exception exc when Lwt.Exception_filter.run exc -> Lwt.reraise exc
let rec unfold_lwt f u () =
let* x = f u in
match x with
| None -> return_nil
| Some (x, u') -> Lwt.return (Cons (x, unfold_lwt f u'))
let unfold_lwt f u () =
let* x = Lwt.apply f u in
match x with
| None -> return_nil
| Some (x, u') -> Lwt.return (Cons (x, unfold_lwt f u'))
let rec of_list l () =
Lwt.return (match l with [] -> Nil | h :: t -> Cons (h, of_list t))
let to_list (seq : 'a t) =
let rec aux f seq =
Lwt.bind (seq ()) (function
| Nil -> Lwt.return (f [])
| Cons (h, t) -> aux (fun x -> f (h :: x)) t)
in
aux (fun x -> x) (Lwt.apply seq)
let rec of_seq seq () =
match seq () with
| Seq.Nil -> return_nil
| Seq.Cons (x, next) ->
Lwt.return (Cons (x, (of_seq next)))
| exception exn when Lwt.Exception_filter.run exn -> Lwt.reraise exn
let rec of_seq_lwt (seq: 'a Lwt.t Seq.t): 'a t = fun () ->
match seq () with
| Seq.Nil -> return_nil
| Seq.Cons (x, next) ->
let+ x = x in
let next = of_seq_lwt next in
Cons (x, next)
let of_seq_lwt (seq: 'a Lwt.t Seq.t): 'a t = fun () ->
match seq () with
| Seq.Nil -> return_nil
| Seq.Cons (x, next) ->
let+ x = x in
let next = of_seq_lwt next in
Cons (x, next)
| exception exc when Lwt.Exception_filter.run exc -> Lwt.reraise exc