Source file read.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
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
open Core
exception Bad_csv_formatting = Parse_state.Bad_csv_formatting
module On_invalid_row = struct
type 'a t =
line_number:int
-> int String.Map.t
-> string Append_only_buffer.t
-> exn
-> [ `Skip | `Yield of 'a | `Raise of exn | `Fallback of 'a t ]
let raise ~line_number buffer exn =
`Raise
(Exn.create_s
[%message
"Exception raised in Delimited.Read"
(line_number : int)
(header_map : int String.Map.t)
~buffer:(Append_only_buffer.to_list buffer : string list)
(exn : exn)])
;;
let skip ~line_number:_ _ _ _ = `Skip
let create = Fn.id
end
module Builder = struct
module T = struct
type _ t =
| Column : int -> string t
| Return : 'a -> 'a t
| Apply : ('b -> 'a) t * 'b t -> 'a t
| Map : ('b -> 'a) * 'b t -> 'a t
| Map2 : ('b -> 'c -> 'a) * 'b t * 'c t -> 'a t
| Both : 'a t * 'b t -> ('a * 'b) t
| Lambda : (int String.Map.t -> string Append_only_buffer.t -> 'a) -> 'a t
let return x = Return x
let apply f x =
match f with
| Return f -> Map (f, x)
| Map (f, w) -> Map2 (f, w, x)
| _ -> Apply (f, x)
;;
let map x ~f =
match x with
| Return x -> Return (f x)
| _ -> Map (f, x)
;;
let ( >>| ) t f = map t ~f
let map2 x y ~f =
match x, y with
| Return x, Return y -> Return (f x y)
| _ -> Map2 (f, x, y)
;;
let map3 x y z ~f =
match x, y, z with
| Return x, Return y, Return z -> Return (f x y z)
| _ -> Apply (Map2 (f, x, y), z)
;;
let all ts = List.fold_right ts ~init:(return []) ~f:(map2 ~f:(fun x xs -> x :: xs))
let all_unit ts = map ~f:ignore (all ts)
let both x y = Both (x, y)
let ( <*> ) = apply
let ( *> ) u v = return (fun () y -> y) <*> u <*> v
let ( <* ) u v = return (fun x () -> x) <*> u <*> v
module Applicative_infix = struct
let ( <*> ) = ( <*> )
let ( *> ) = ( *> )
let ( <* ) = ( <* )
let ( >>| ) = ( >>| )
end
end
include T
let at_index i ~f = Map (f, Column i)
let h ~f = Map (f, Header h)
let h ~f = Map (f, Header_opt h)
let lambda f = Lambda f
module Record_builder = Record_builder.Make (T)
module Fields_O = struct
let ( !! ) of_string field =
Record_builder.field (at_header (Field.name field) ~f:of_string) field
;;
let ( !? ) of_string field =
Record_builder.field (at_header_opt (Field.name field) ~f:of_string) field
;;
end
module Open_on_rhs_intf = struct
module type S = Read_intf.Open_on_rhs with type 'a t := 'a t
end
module Let_syntax = struct
include T
include Applicative_infix
module Let_syntax = struct
include T
module Open_on_rhs = struct
let at_index = at_index
let = at_header
let = at_header_opt
end
end
end
let build ~ t =
let rec transform : type a. a t -> a Without_headers.t = function
| Return x -> Without_headers.Return x
| Column i -> Without_headers.Column i
| Header column ->
(match Map.find_exn (header_map : _ String.Map.t) column with
| index -> Without_headers.Column index
| exception (Not_found_s _ | Stdlib.Not_found) ->
raise_s
[%message
"Missing column in header"
(column : string)
(header_map : int String.Map.t)])
| Header_opt h ->
(match Map.find_exn (header_map : _ String.Map.t) h with
| index -> Without_headers.Map (Option.some, Column index)
| exception (Not_found_s _ | Stdlib.Not_found) -> Without_headers.Return None)
| Apply (f, x) -> Without_headers.Apply (transform f, transform x)
| Map (f, x) -> Without_headers.Map (f, transform x)
| Map2 (f, x, y) -> Without_headers.Map2 (f, transform x, transform y)
| Both (x, y) -> Without_headers.Both (transform x, transform y)
| Lambda f -> Without_headers.Lambda (f, header_map)
in
let transformed = transform t in
Without_headers.build transformed
;;
end
include Builder
next_line_number : int
; consumed : int
}
[@@deriving sexp_of]
end
let ~foldi =
foldi header_row ~init:String.Map.empty ~f:(fun i map ->
Map.set map ~key:header ~data:i)
;;
let =
let = String.Set.of_list required_headers' in
let = String.Set.of_array csv_headers' in
let missing = Set.diff required_headers csv_headers in
if not (Set.is_empty missing)
then
raise_s
[%message
"Header specified in `Require not present in csv document"
(required_headers : String.Set.t)
(csv_headers : String.Set.t)
(missing : String.Set.t)];
header_map ~foldi:Array.foldi csv_headers'
;;
let ?strip ?sep ?quote ?start_line_number transform : Partial.t =
let f ~line_number:_ r row =
match r with
| Some _ -> raise_s [%message "Header already parsed, cannot feed more input"]
| None -> Some (Append_only_buffer.to_array row)
in
{ state =
Parse_state.create
?strip
?sep
?quote
?start_line_number
~fields_used:None
~init:None
~f
()
; transform
}
;;
let ?strip ?sep ?quote ?(start_line_number = 1) ?( = `No) () =
match header with
| `No ->
Second
{ Success.header_map = String.Map.empty
; next_line_number = start_line_number
; consumed = 0
}
| `Add ->
Second
{ header_map = header_map ~foldi:List.foldi headers
; next_line_number = start_line_number
; consumed = 0
}
| `Yes ->
let f = header_map ~foldi:Array.foldi headers in
First (create' ?strip ?sep ?quote ~start_line_number f)
| `Require ->
let f = require_header headers csv_headers in
First (create' ?strip ?sep ?quote ~start_line_number f)
| `Replace ->
let f _ = header_map ~foldi:List.foldi headers in
First (create' ?strip ?sep ?quote ~start_line_number f)
| `Transform f ->
let f = header_map ~foldi:List.foldi (f (Array.to_list headers)) in
First (create' ?strip ?sep ?quote ~start_line_number f)
| `Filter_map f ->
let foldi l ~init ~f =
List.foldi l ~init ~f:(fun i acc x ->
match x with
| None -> acc
| Some x -> f i acc x) [@nontail]
in
let f = header_map ~foldi (f (Array.to_list headers)) in
First (create' ?strip ?sep ?quote ~start_line_number f)
;;
let (t : Partial.t) =
match Parse_state.acc t.state with
| Some row -> Some (t, row)
| None -> None
;;
let (t : Partial.t) ?(pos = 0) ?len input : _ Either.t =
match is_set t with
| Some _ -> raise_s [%message "Header already parsed, cannot feed more input"]
| None ->
let len =
match len with
| None -> String.length input - pos
| Some len -> len
in
let start_pos = pos in
let max_pos = start_pos + len in
if start_pos < 0 || len < 0 || max_pos > String.length input
then
invalid_arg
"Delimited_kernel.Read.Expert.Parse_header.input_string: index out of bound";
let rec loop (t : Partial.t) ~pos ~len =
if pos >= max_pos
then First t
else (
let end_pos =
match String.index_from input pos '\n' with
| None -> max_pos
| Some end_pos -> min max_pos (end_pos + 1)
in
let line_len = end_pos - pos in
let t =
{ t with state = Parse_state.input_string t.state ~pos ~len:line_len input }
in
match is_set t with
| None -> loop t ~pos:end_pos ~len:(len - line_len)
| Some (t, row) ->
Second
{ Success.header_map = t.transform row
; consumed = end_pos - start_pos
; next_line_number = Parse_state.current_line_number t.state
})
in
loop t ~pos ~len
;;
let (t : Partial.t) =
let t = { t with state = Parse_state.finish t.state } in
match is_set t with
| Some (t, row) ->
{ Success.header_map = t.transform row
; consumed = 0
; next_line_number = Parse_state.current_line_number t.state
}
| None ->
if Parse_state.at_beginning_of_row t.state
then
{ Success.header_map = t.transform [| "" |]
; consumed = 0
; next_line_number = Parse_state.current_line_number t.state
}
else
assert false
;;
end
module Streaming = struct
type 'a builder_t = 'a t
type 'a t =
| Parsing_rows of
{ header_map : int String.Map.t
; state : 'a Parse_state.t
}
let create_indexed
?strip
?sep
?quote
?start_line_number
?(on_invalid_row = (On_invalid_row.raise : _ On_invalid_row.t))
?( : Header.t option)
builder
~init
~f
=
let mk_state init ?start_line_number =
let row_to_'a, fields_used = Builder.build ~header_map builder in
let f ~line_number init row =
try f line_number init (row_to_'a row) with
| exn ->
let rec loop on_invalid_row =
match on_invalid_row ~line_number header_map row exn with
| `Yield x -> f line_number init x
| `Skip -> init
| `Fallback on_invalid_row -> loop on_invalid_row
| `Raise exn -> raise exn
in
loop on_invalid_row
in
Parse_state.create ?strip ?sep ?quote ?start_line_number ~fields_used ~init ~f ()
in
match Parse_header.create ?strip ?sep ?quote ?start_line_number ?header () with
| First partial -> Parsing_header { partial; mk_state; init }
| Second { ; consumed = _; next_line_number } ->
let state = mk_state init ~start_line_number:next_line_number header_map in
Parsing_rows { header_map; state }
;;
let create
?strip
?sep
?quote
?start_line_number
?on_invalid_row
?
builder
~init
~f
=
create_indexed
?strip
?sep
?quote
?start_line_number
?on_invalid_row
?header
builder
~init
~f:(fun (_ : int) -> f)
;;
let input_string t ?(pos = 0) ?len input =
let len =
match len with
| None -> String.length input - pos
| Some len -> len
in
match t with
| Parsing_header { partial; mk_state; init } ->
(match Parse_header.input_string partial ~pos ~len input with
| First partial -> Parsing_header { partial; mk_state; init }
| Second { consumed; ; next_line_number } ->
let state = mk_state init header_map ~start_line_number:next_line_number in
let state =
Parse_state.input_string
state
~pos:(pos + consumed)
~len:(len - consumed)
input
in
Parsing_rows { header_map; state })
| Parsing_rows { ; state } ->
Parsing_rows { header_map; state = Parse_state.input_string state ~pos ~len input }
;;
let input t ?pos ?len input =
input_string
t
?pos
?len
(Bytes.unsafe_to_string ~no_mutation_while_string_reachable:input)
;;
let finish t =
match t with
| Parsing_header { partial; mk_state; init } ->
let { Parse_header.Success.consumed = _; ; next_line_number } =
Parse_header.finish_exn partial
in
let state =
Parse_state.finish (mk_state init header_map ~start_line_number:next_line_number)
in
Parsing_rows { state; header_map }
| Parsing_rows { state; } ->
Parsing_rows { state = Parse_state.finish state; header_map }
;;
let acc t =
match t with
| Parsing_header { init; _ } -> init
| Parsing_rows { state; _ } -> Parse_state.acc state
;;
let state t =
match t with
| Parsing_header _ -> `Parsing_header
| Parsing_rows _ -> `Parsing_rows
;;
let t =
match t with
| Parsing_header _ -> None
| Parsing_rows { ; _ } -> Some (Map.key_set header_map)
;;
end
module Expert = struct
module Append_only_buffer = Append_only_buffer
module Parse_state = Parse_state
module Builder = Builder
end
let fold_string ?strip ?sep ?quote ? ?on_invalid_row builder ~init ~f csv_string =
let state =
Streaming.create ?strip ?sep ?quote ?header ?on_invalid_row builder ~init ~f
in
Streaming.input_string state csv_string |> Streaming.finish |> Streaming.acc
;;
let list_of_string ?strip ?sep ?quote ? ?on_invalid_row builder csv_string =
fold_string
?strip
?sep
?quote
?header
?on_invalid_row
builder
csv_string
~init:(Append_only_buffer.create ())
~f:(fun queue row ->
Append_only_buffer.append queue row;
queue)
|> Append_only_buffer.to_list
;;
let read_lines ?strip ?sep ?quote ? ?on_invalid_row builder in_channel =
let contents = In_channel.input_all in_channel in
list_of_string ?strip ?sep ?quote ?header ?on_invalid_row builder contents
;;
let fold_lines
?(buffer_size = 8192)
?strip
?sep
?quote
?
?on_invalid_row
builder
~init
~f
in_channel
=
let buf = Bytes.create buffer_size in
let rec loop state =
match In_channel.input in_channel ~buf ~pos:0 ~len:buffer_size with
| 0 -> state
| len ->
Streaming.input_string
state
~len
(Bytes.unsafe_to_string ~no_mutation_while_string_reachable:buf)
|> loop
in
Streaming.create ?strip ?sep ?quote ?header ?on_invalid_row builder ~init ~f
|> loop
|> Streaming.finish
|> Streaming.acc
;;
module Row = struct
type 'a builder_t = 'a t
include Row
let builder = lambda Row.Expert.of_buffer
end