forked from microsoft/TypeScript
-
Notifications
You must be signed in to change notification settings - Fork 1
Expand file tree
/
Copy pathcore.ts
More file actions
2334 lines (2089 loc) · 94.8 KB
/
core.ts
File metadata and controls
2334 lines (2089 loc) · 94.8 KB
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
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
/* @internal */
namespace ts {
export function getIterator<I extends readonly any[] | ReadonlySet<any> | ReadonlyESMap<any, any> | undefined>(iterable: I): Iterator<
I extends ReadonlyESMap<infer K, infer V> ? [K, V] :
I extends ReadonlySet<infer T> ? T :
I extends readonly (infer T)[] ? T :
I extends undefined ? undefined :
never>;
export function getIterator<K, V>(iterable: ReadonlyESMap<K, V>): Iterator<[K, V]>;
export function getIterator<K, V>(iterable: ReadonlyESMap<K, V> | undefined): Iterator<[K, V]> | undefined;
export function getIterator<T>(iterable: readonly T[] | ReadonlySet<T>): Iterator<T>;
export function getIterator<T>(iterable: readonly T[] | ReadonlySet<T> | undefined): Iterator<T> | undefined;
export function getIterator(iterable: readonly any[] | ReadonlySet<any> | ReadonlyESMap<any, any> | undefined): Iterator<any> | undefined {
if (iterable) {
if (isArray(iterable)) return arrayIterator(iterable);
if (iterable instanceof Map) return iterable.entries();
if (iterable instanceof Set) return iterable.values();
throw new Error("Iteration not supported.");
}
}
export const emptyArray: never[] = [] as never[];
export const emptyMap: ReadonlyESMap<never, never> = new Map<never, never>();
export const emptySet: ReadonlySet<never> = new Set<never>();
/**
* Create a new map.
* @deprecated Use `new Map()` instead.
*/
export function createMap<K, V>(): ESMap<K, V>;
export function createMap<T>(): ESMap<string, T>;
export function createMap<K, V>(): ESMap<K, V> {
return new Map<K, V>();
}
/**
* Create a new map from a template object is provided, the map will copy entries from it.
* @deprecated Use `new Map(getEntries(template))` instead.
*/
export function createMapFromTemplate<T>(template: MapLike<T>): ESMap<string, T> {
const map: ESMap<string, T> = new Map<string, T>();
// Copies keys/values from template. Note that for..in will not throw if
// template is undefined, and instead will just exit the loop.
for (const key in template) {
if (hasOwnProperty.call(template, key)) {
map.set(key, template[key]);
}
}
return map;
}
export function length(array: readonly any[] | undefined): number {
return array ? array.length : 0;
}
/**
* Iterates through 'array' by index and performs the callback on each element of array until the callback
* returns a truthy value, then returns that value.
* If no such value is found, the callback is applied to each element of array and undefined is returned.
*/
export function forEach<T, U>(array: readonly T[] | undefined, callback: (element: T, index: number) => U | undefined): U | undefined {
if (array) {
for (let i = 0; i < array.length; i++) {
const result = callback(array[i], i);
if (result) {
return result;
}
}
}
return undefined;
}
/**
* Like `forEach`, but iterates in reverse order.
*/
export function forEachRight<T, U>(array: readonly T[] | undefined, callback: (element: T, index: number) => U | undefined): U | undefined {
if (array) {
for (let i = array.length - 1; i >= 0; i--) {
const result = callback(array[i], i);
if (result) {
return result;
}
}
}
return undefined;
}
/** Like `forEach`, but suitable for use with numbers and strings (which may be falsy). */
export function firstDefined<T, U>(array: readonly T[] | undefined, callback: (element: T, index: number) => U | undefined): U | undefined {
if (array === undefined) {
return undefined;
}
for (let i = 0; i < array.length; i++) {
const result = callback(array[i], i);
if (result !== undefined) {
return result;
}
}
return undefined;
}
export function firstDefinedIterator<T, U>(iter: Iterator<T>, callback: (element: T) => U | undefined): U | undefined {
while (true) {
const iterResult = iter.next();
if (iterResult.done) {
return undefined;
}
const result = callback(iterResult.value);
if (result !== undefined) {
return result;
}
}
}
export function reduceLeftIterator<T, U>(iterator: Iterator<T> | undefined, f: (memo: U, value: T, i: number) => U, initial: U): U {
let result = initial;
if (iterator) {
for (let step = iterator.next(), pos = 0; !step.done; step = iterator.next(), pos++) {
result = f(result, step.value, pos);
}
}
return result;
}
export function zipWith<T, U, V>(arrayA: readonly T[], arrayB: readonly U[], callback: (a: T, b: U, index: number) => V): V[] {
const result: V[] = [];
Debug.assertEqual(arrayA.length, arrayB.length);
for (let i = 0; i < arrayA.length; i++) {
result.push(callback(arrayA[i], arrayB[i], i));
}
return result;
}
export function zipToIterator<T, U>(arrayA: readonly T[], arrayB: readonly U[]): Iterator<[T, U]> {
Debug.assertEqual(arrayA.length, arrayB.length);
let i = 0;
return {
next() {
if (i === arrayA.length) {
return { value: undefined as never, done: true };
}
i++;
return { value: [arrayA[i - 1], arrayB[i - 1]] as [T, U], done: false };
}
};
}
export function zipToMap<K, V>(keys: readonly K[], values: readonly V[]): ESMap<K, V> {
Debug.assert(keys.length === values.length);
const map = new Map<K, V>();
for (let i = 0; i < keys.length; ++i) {
map.set(keys[i], values[i]);
}
return map;
}
/**
* Creates a new array with `element` interspersed in between each element of `input`
* if there is more than 1 value in `input`. Otherwise, returns the existing array.
*/
export function intersperse<T>(input: T[], element: T): T[] {
if (input.length <= 1) {
return input;
}
const result: T[] = [];
for (let i = 0, n = input.length; i < n; i++) {
if (i) result.push(element);
result.push(input[i]);
}
return result;
}
/**
* Iterates through `array` by index and performs the callback on each element of array until the callback
* returns a falsey value, then returns false.
* If no such value is found, the callback is applied to each element of array and `true` is returned.
*/
export function every<T>(array: readonly T[] | undefined, callback: (element: T, index: number) => boolean): boolean {
if (array) {
for (let i = 0; i < array.length; i++) {
if (!callback(array[i], i)) {
return false;
}
}
}
return true;
}
/** Works like Array.prototype.find, returning `undefined` if no element satisfying the predicate is found. */
export function find<T, U extends T>(array: readonly T[], predicate: (element: T, index: number) => element is U): U | undefined;
export function find<T>(array: readonly T[], predicate: (element: T, index: number) => boolean): T | undefined;
export function find<T>(array: readonly T[], predicate: (element: T, index: number) => boolean): T | undefined {
for (let i = 0; i < array.length; i++) {
const value = array[i];
if (predicate(value, i)) {
return value;
}
}
return undefined;
}
export function findLast<T, U extends T>(array: readonly T[], predicate: (element: T, index: number) => element is U): U | undefined;
export function findLast<T>(array: readonly T[], predicate: (element: T, index: number) => boolean): T | undefined;
export function findLast<T>(array: readonly T[], predicate: (element: T, index: number) => boolean): T | undefined {
for (let i = array.length - 1; i >= 0; i--) {
const value = array[i];
if (predicate(value, i)) {
return value;
}
}
return undefined;
}
/** Works like Array.prototype.findIndex, returning `-1` if no element satisfying the predicate is found. */
export function findIndex<T>(array: readonly T[], predicate: (element: T, index: number) => boolean, startIndex?: number): number {
for (let i = startIndex || 0; i < array.length; i++) {
if (predicate(array[i], i)) {
return i;
}
}
return -1;
}
export function findLastIndex<T>(array: readonly T[], predicate: (element: T, index: number) => boolean, startIndex?: number): number {
for (let i = startIndex === undefined ? array.length - 1 : startIndex; i >= 0; i--) {
if (predicate(array[i], i)) {
return i;
}
}
return -1;
}
/**
* Returns the first truthy result of `callback`, or else fails.
* This is like `forEach`, but never returns undefined.
*/
export function findMap<T, U>(array: readonly T[], callback: (element: T, index: number) => U | undefined): U {
for (let i = 0; i < array.length; i++) {
const result = callback(array[i], i);
if (result) {
return result;
}
}
return Debug.fail();
}
export function contains<T>(array: readonly T[] | undefined, value: T, equalityComparer: EqualityComparer<T> = equateValues): boolean {
if (array) {
for (const v of array) {
if (equalityComparer(v, value)) {
return true;
}
}
}
return false;
}
export function arraysEqual<T>(a: readonly T[], b: readonly T[], equalityComparer: EqualityComparer<T> = equateValues): boolean {
return a.length === b.length && a.every((x, i) => equalityComparer(x, b[i]));
}
export function indexOfAnyCharCode(text: string, charCodes: readonly number[], start?: number): number {
for (let i = start || 0; i < text.length; i++) {
if (contains(charCodes, text.charCodeAt(i))) {
return i;
}
}
return -1;
}
export function countWhere<T>(array: readonly T[] | undefined, predicate: (x: T, i: number) => boolean): number {
let count = 0;
if (array) {
for (let i = 0; i < array.length; i++) {
const v = array[i];
if (predicate(v, i)) {
count++;
}
}
}
return count;
}
/**
* Filters an array by a predicate function. Returns the same array instance if the predicate is
* true for all elements, otherwise returns a new array instance containing the filtered subset.
*/
export function filter<T, U extends T>(array: T[], f: (x: T) => x is U): U[];
export function filter<T>(array: T[], f: (x: T) => boolean): T[];
export function filter<T, U extends T>(array: readonly T[], f: (x: T) => x is U): readonly U[];
export function filter<T, U extends T>(array: readonly T[], f: (x: T) => boolean): readonly T[];
export function filter<T, U extends T>(array: T[] | undefined, f: (x: T) => x is U): U[] | undefined;
export function filter<T>(array: T[] | undefined, f: (x: T) => boolean): T[] | undefined;
export function filter<T, U extends T>(array: readonly T[] | undefined, f: (x: T) => x is U): readonly U[] | undefined;
export function filter<T, U extends T>(array: readonly T[] | undefined, f: (x: T) => boolean): readonly T[] | undefined;
export function filter<T>(array: readonly T[] | undefined, f: (x: T) => boolean): readonly T[] | undefined {
if (array) {
const len = array.length;
let i = 0;
while (i < len && f(array[i])) i++;
if (i < len) {
const result = array.slice(0, i);
i++;
while (i < len) {
const item = array[i];
if (f(item)) {
result.push(item);
}
i++;
}
return result;
}
}
return array;
}
export function filterMutate<T>(array: T[], f: (x: T, i: number, array: T[]) => boolean): void {
let outIndex = 0;
for (let i = 0; i < array.length; i++) {
if (f(array[i], i, array)) {
array[outIndex] = array[i];
outIndex++;
}
}
array.length = outIndex;
}
export function clear(array: {}[]): void {
array.length = 0;
}
export function map<T, U>(array: readonly T[], f: (x: T, i: number) => U): U[];
export function map<T, U>(array: readonly T[] | undefined, f: (x: T, i: number) => U): U[] | undefined;
export function map<T, U>(array: readonly T[] | undefined, f: (x: T, i: number) => U): U[] | undefined {
let result: U[] | undefined;
if (array) {
result = [];
for (let i = 0; i < array.length; i++) {
result.push(f(array[i], i));
}
}
return result;
}
export function mapIterator<T, U>(iter: Iterator<T>, mapFn: (x: T) => U): Iterator<U> {
return {
next() {
const iterRes = iter.next();
return iterRes.done ? iterRes as { done: true, value: never } : { value: mapFn(iterRes.value), done: false };
}
};
}
// Maps from T to T and avoids allocation if all elements map to themselves
export function sameMap<T>(array: T[], f: (x: T, i: number) => T): T[];
export function sameMap<T>(array: readonly T[], f: (x: T, i: number) => T): readonly T[];
export function sameMap<T>(array: T[] | undefined, f: (x: T, i: number) => T): T[] | undefined;
export function sameMap<T>(array: readonly T[] | undefined, f: (x: T, i: number) => T): readonly T[] | undefined;
export function sameMap<T>(array: readonly T[] | undefined, f: (x: T, i: number) => T): readonly T[] | undefined {
if (array) {
for (let i = 0; i < array.length; i++) {
const item = array[i];
const mapped = f(item, i);
if (item !== mapped) {
const result = array.slice(0, i);
result.push(mapped);
for (i++; i < array.length; i++) {
result.push(f(array[i], i));
}
return result;
}
}
}
return array;
}
/**
* Flattens an array containing a mix of array or non-array elements.
*
* @param array The array to flatten.
*/
export function flatten<T>(array: T[][] | readonly (T | readonly T[] | undefined)[]): T[] {
const result = [];
for (const v of array) {
if (v) {
if (isArray(v)) {
addRange(result, v);
}
else {
result.push(v);
}
}
}
return result;
}
/**
* Maps an array. If the mapped value is an array, it is spread into the result.
*
* @param array The array to map.
* @param mapfn The callback used to map the result into one or more values.
*/
export function flatMap<T, U>(array: readonly T[] | undefined, mapfn: (x: T, i: number) => U | readonly U[] | undefined): readonly U[] {
let result: U[] | undefined;
if (array) {
for (let i = 0; i < array.length; i++) {
const v = mapfn(array[i], i);
if (v) {
if (isArray(v)) {
result = addRange(result, v);
}
else {
result = append(result, v);
}
}
}
}
return result || emptyArray;
}
export function flatMapToMutable<T, U>(array: readonly T[] | undefined, mapfn: (x: T, i: number) => U | readonly U[] | undefined): U[] {
const result: U[] = [];
if (array) {
for (let i = 0; i < array.length; i++) {
const v = mapfn(array[i], i);
if (v) {
if (isArray(v)) {
addRange(result, v);
}
else {
result.push(v);
}
}
}
}
return result;
}
export function flatMapIterator<T, U>(iter: Iterator<T>, mapfn: (x: T) => readonly U[] | Iterator<U> | undefined): Iterator<U> {
const first = iter.next();
if (first.done) {
return emptyIterator;
}
let currentIter = getIterator(first.value);
return {
next() {
while (true) {
const currentRes = currentIter.next();
if (!currentRes.done) {
return currentRes;
}
const iterRes = iter.next();
if (iterRes.done) {
return iterRes as { done: true, value: never };
}
currentIter = getIterator(iterRes.value);
}
},
};
function getIterator(x: T): Iterator<U> {
const res = mapfn(x);
return res === undefined ? emptyIterator : isArray(res) ? arrayIterator(res) : res;
}
}
/**
* Maps an array. If the mapped value is an array, it is spread into the result.
* Avoids allocation if all elements map to themselves.
*
* @param array The array to map.
* @param mapfn The callback used to map the result into one or more values.
*/
export function sameFlatMap<T>(array: T[], mapfn: (x: T, i: number) => T | readonly T[]): T[];
export function sameFlatMap<T>(array: readonly T[], mapfn: (x: T, i: number) => T | readonly T[]): readonly T[];
export function sameFlatMap<T>(array: T[], mapfn: (x: T, i: number) => T | T[]): T[] {
let result: T[] | undefined;
if (array) {
for (let i = 0; i < array.length; i++) {
const item = array[i];
const mapped = mapfn(item, i);
if (result || item !== mapped || isArray(mapped)) {
if (!result) {
result = array.slice(0, i);
}
if (isArray(mapped)) {
addRange(result, mapped);
}
else {
result.push(mapped);
}
}
}
}
return result || array;
}
export function mapAllOrFail<T, U>(array: readonly T[], mapFn: (x: T, i: number) => U | undefined): U[] | undefined {
const result: U[] = [];
for (let i = 0; i < array.length; i++) {
const mapped = mapFn(array[i], i);
if (mapped === undefined) {
return undefined;
}
result.push(mapped);
}
return result;
}
export function mapDefined<T, U>(array: readonly T[] | undefined, mapFn: (x: T, i: number) => U | undefined): U[] {
const result: U[] = [];
if (array) {
for (let i = 0; i < array.length; i++) {
const mapped = mapFn(array[i], i);
if (mapped !== undefined) {
result.push(mapped);
}
}
}
return result;
}
export function mapDefinedIterator<T, U>(iter: Iterator<T>, mapFn: (x: T) => U | undefined): Iterator<U> {
return {
next() {
while (true) {
const res = iter.next();
if (res.done) {
return res as { done: true, value: never };
}
const value = mapFn(res.value);
if (value !== undefined) {
return { value, done: false };
}
}
}
};
}
export function mapDefinedEntries<K1, V1, K2, V2>(map: ReadonlyESMap<K1, V1>, f: (key: K1, value: V1) => readonly [K2, V2] | undefined): ESMap<K2, V2>;
export function mapDefinedEntries<K1, V1, K2, V2>(map: ReadonlyESMap<K1, V1> | undefined, f: (key: K1, value: V1) => readonly [K2 | undefined, V2 | undefined] | undefined): ESMap<K2, V2> | undefined;
export function mapDefinedEntries<K1, V1, K2, V2>(map: ReadonlyESMap<K1, V1> | undefined, f: (key: K1, value: V1) => readonly [K2 | undefined, V2 | undefined] | undefined): ESMap<K2, V2> | undefined {
if (!map) {
return undefined;
}
const result = new Map<K2, V2>();
map.forEach((value, key) => {
const entry = f(key, value);
if (entry !== undefined) {
const [newKey, newValue] = entry;
if (newKey !== undefined && newValue !== undefined) {
result.set(newKey, newValue);
}
}
});
return result;
}
export function mapDefinedValues<V1, V2>(set: ReadonlySet<V1>, f: (value: V1) => V2 | undefined): Set<V2>;
export function mapDefinedValues<V1, V2>(set: ReadonlySet<V1> | undefined, f: (value: V1) => V2 | undefined): Set<V2> | undefined;
export function mapDefinedValues<V1, V2>(set: ReadonlySet<V1> | undefined, f: (value: V1) => V2 | undefined): Set<V2> | undefined {
if (set) {
const result = new Set<V2>();
set.forEach(value => {
const newValue = f(value);
if (newValue !== undefined) {
result.add(newValue);
}
});
return result;
}
}
export function getOrUpdate<K, V>(map: ESMap<K, V>, key: K, callback: () => V) {
if (map.has(key)) {
return map.get(key)!;
}
const value = callback();
map.set(key, value);
return value;
}
export function tryAddToSet<T>(set: Set<T>, value: T) {
if (!set.has(value)) {
set.add(value);
return true;
}
return false;
}
export const emptyIterator: Iterator<never> = { next: () => ({ value: undefined as never, done: true }) };
export function singleIterator<T>(value: T): Iterator<T> {
let done = false;
return {
next() {
const wasDone = done;
done = true;
return wasDone ? { value: undefined as never, done: true } : { value, done: false };
}
};
}
/**
* Maps contiguous spans of values with the same key.
*
* @param array The array to map.
* @param keyfn A callback used to select the key for an element.
* @param mapfn A callback used to map a contiguous chunk of values to a single value.
*/
export function spanMap<T, K, U>(array: readonly T[], keyfn: (x: T, i: number) => K, mapfn: (chunk: T[], key: K, start: number, end: number) => U): U[];
export function spanMap<T, K, U>(array: readonly T[] | undefined, keyfn: (x: T, i: number) => K, mapfn: (chunk: T[], key: K, start: number, end: number) => U): U[] | undefined;
export function spanMap<T, K, U>(array: readonly T[] | undefined, keyfn: (x: T, i: number) => K, mapfn: (chunk: T[], key: K, start: number, end: number) => U): U[] | undefined {
let result: U[] | undefined;
if (array) {
result = [];
const len = array.length;
let previousKey: K | undefined;
let key: K | undefined;
let start = 0;
let pos = 0;
while (start < len) {
while (pos < len) {
const value = array[pos];
key = keyfn(value, pos);
if (pos === 0) {
previousKey = key;
}
else if (key !== previousKey) {
break;
}
pos++;
}
if (start < pos) {
const v = mapfn(array.slice(start, pos), previousKey!, start, pos);
if (v) {
result.push(v);
}
start = pos;
}
previousKey = key;
pos++;
}
}
return result;
}
export function mapEntries<K1, V1, K2, V2>(map: ReadonlyESMap<K1, V1>, f: (key: K1, value: V1) => readonly [K2, V2]): ESMap<K2, V2>;
export function mapEntries<K1, V1, K2, V2>(map: ReadonlyESMap<K1, V1> | undefined, f: (key: K1, value: V1) => readonly [K2, V2]): ESMap<K2, V2> | undefined;
export function mapEntries<K1, V1, K2, V2>(map: ReadonlyESMap<K1, V1> | undefined, f: (key: K1, value: V1) => readonly [K2, V2]): ESMap<K2, V2> | undefined {
if (!map) {
return undefined;
}
const result = new Map<K2, V2>();
map.forEach((value, key) => {
const [newKey, newValue] = f(key, value);
result.set(newKey, newValue);
});
return result;
}
export function some<T>(array: readonly T[] | undefined): array is readonly T[];
export function some<T>(array: readonly T[] | undefined, predicate: (value: T) => boolean): boolean;
export function some<T>(array: readonly T[] | undefined, predicate?: (value: T) => boolean): boolean {
if (array) {
if (predicate) {
for (const v of array) {
if (predicate(v)) {
return true;
}
}
}
else {
return array.length > 0;
}
}
return false;
}
/** Calls the callback with (start, afterEnd) index pairs for each range where 'pred' is true. */
export function getRangesWhere<T>(arr: readonly T[], pred: (t: T) => boolean, cb: (start: number, afterEnd: number) => void): void {
let start: number | undefined;
for (let i = 0; i < arr.length; i++) {
if (pred(arr[i])) {
start = start === undefined ? i : start;
}
else {
if (start !== undefined) {
cb(start, i);
start = undefined;
}
}
}
if (start !== undefined) cb(start, arr.length);
}
export function concatenate<T>(array1: T[], array2: T[]): T[];
export function concatenate<T>(array1: readonly T[], array2: readonly T[]): readonly T[];
export function concatenate<T>(array1: T[] | undefined, array2: T[] | undefined): T[];
export function concatenate<T>(array1: readonly T[] | undefined, array2: readonly T[] | undefined): readonly T[];
export function concatenate<T>(array1: T[], array2: T[]): T[] {
if (!some(array2)) return array1;
if (!some(array1)) return array2;
return [...array1, ...array2];
}
function selectIndex(_: unknown, i: number) {
return i;
}
export function indicesOf(array: readonly unknown[]): number[] {
return array.map(selectIndex);
}
function deduplicateRelational<T>(array: readonly T[], equalityComparer: EqualityComparer<T>, comparer: Comparer<T>) {
// Perform a stable sort of the array. This ensures the first entry in a list of
// duplicates remains the first entry in the result.
const indices = indicesOf(array);
stableSortIndices(array, indices, comparer);
let last = array[indices[0]];
const deduplicated: number[] = [indices[0]];
for (let i = 1; i < indices.length; i++) {
const index = indices[i];
const item = array[index];
if (!equalityComparer(last, item)) {
deduplicated.push(index);
last = item;
}
}
// restore original order
deduplicated.sort();
return deduplicated.map(i => array[i]);
}
function deduplicateEquality<T>(array: readonly T[], equalityComparer: EqualityComparer<T>) {
const result: T[] = [];
for (const item of array) {
pushIfUnique(result, item, equalityComparer);
}
return result;
}
/**
* Deduplicates an unsorted array.
* @param equalityComparer An `EqualityComparer` used to determine if two values are duplicates.
* @param comparer An optional `Comparer` used to sort entries before comparison, though the
* result will remain in the original order in `array`.
*/
export function deduplicate<T>(array: readonly T[], equalityComparer: EqualityComparer<T>, comparer?: Comparer<T>): T[] {
return array.length === 0 ? [] :
array.length === 1 ? array.slice() :
comparer ? deduplicateRelational(array, equalityComparer, comparer) :
deduplicateEquality(array, equalityComparer);
}
/**
* Deduplicates an array that has already been sorted.
*/
function deduplicateSorted<T>(array: SortedReadonlyArray<T>, comparer: EqualityComparer<T> | Comparer<T>): SortedReadonlyArray<T> {
if (array.length === 0) return emptyArray as any as SortedReadonlyArray<T>;
let last = array[0];
const deduplicated: T[] = [last];
for (let i = 1; i < array.length; i++) {
const next = array[i];
switch (comparer(next, last)) {
// equality comparison
case true:
// relational comparison
// falls through
case Comparison.EqualTo:
continue;
case Comparison.LessThan:
// If `array` is sorted, `next` should **never** be less than `last`.
return Debug.fail("Array is unsorted.");
}
deduplicated.push(last = next);
}
return deduplicated as any as SortedReadonlyArray<T>;
}
export function insertSorted<T>(array: SortedArray<T>, insert: T, compare: Comparer<T>): void {
if (array.length === 0) {
array.push(insert);
return;
}
const insertIndex = binarySearch(array, insert, identity, compare);
if (insertIndex < 0) {
array.splice(~insertIndex, 0, insert);
}
}
export function sortAndDeduplicate<T>(array: readonly string[]): SortedReadonlyArray<string>;
export function sortAndDeduplicate<T>(array: readonly T[], comparer: Comparer<T>, equalityComparer?: EqualityComparer<T>): SortedReadonlyArray<T>;
export function sortAndDeduplicate<T>(array: readonly T[], comparer?: Comparer<T>, equalityComparer?: EqualityComparer<T>): SortedReadonlyArray<T> {
return deduplicateSorted(sort(array, comparer), equalityComparer || comparer || compareStringsCaseSensitive as any as Comparer<T>);
}
export function arrayIsSorted<T>(array: readonly T[], comparer: Comparer<T>) {
if (array.length < 2) return true;
let prevElement = array[0];
for (const element of array.slice(1)) {
if (comparer(prevElement, element) === Comparison.GreaterThan) {
return false;
}
prevElement = element;
}
return true;
}
export function arrayIsEqualTo<T>(array1: readonly T[] | undefined, array2: readonly T[] | undefined, equalityComparer: (a: T, b: T, index: number) => boolean = equateValues): boolean {
if (!array1 || !array2) {
return array1 === array2;
}
if (array1.length !== array2.length) {
return false;
}
for (let i = 0; i < array1.length; i++) {
if (!equalityComparer(array1[i], array2[i], i)) {
return false;
}
}
return true;
}
/**
* Compacts an array, removing any falsey elements.
*/
export function compact<T>(array: (T | undefined | null | false | 0 | "")[]): T[];
export function compact<T>(array: readonly (T | undefined | null | false | 0 | "")[]): readonly T[];
// ESLint thinks these can be combined with the above - they cannot; they'd produce higher-priority inferences and prevent the falsey types from being stripped
export function compact<T>(array: T[]): T[]; // eslint-disable-line @typescript-eslint/unified-signatures
export function compact<T>(array: readonly T[]): readonly T[]; // eslint-disable-line @typescript-eslint/unified-signatures
export function compact<T>(array: T[]): T[] {
let result: T[] | undefined;
if (array) {
for (let i = 0; i < array.length; i++) {
const v = array[i];
if (result || !v) {
if (!result) {
result = array.slice(0, i);
}
if (v) {
result.push(v);
}
}
}
}
return result || array;
}
/**
* Gets the relative complement of `arrayA` with respect to `arrayB`, returning the elements that
* are not present in `arrayA` but are present in `arrayB`. Assumes both arrays are sorted
* based on the provided comparer.
*/
export function relativeComplement<T>(arrayA: T[] | undefined, arrayB: T[] | undefined, comparer: Comparer<T>): T[] | undefined {
if (!arrayB || !arrayA || arrayB.length === 0 || arrayA.length === 0) return arrayB;
const result: T[] = [];
loopB: for (let offsetA = 0, offsetB = 0; offsetB < arrayB.length; offsetB++) {
if (offsetB > 0) {
// Ensure `arrayB` is properly sorted.
Debug.assertGreaterThanOrEqual(comparer(arrayB[offsetB], arrayB[offsetB - 1]), Comparison.EqualTo);
}
loopA: for (const startA = offsetA; offsetA < arrayA.length; offsetA++) {
if (offsetA > startA) {
// Ensure `arrayA` is properly sorted. We only need to perform this check if
// `offsetA` has changed since we entered the loop.
Debug.assertGreaterThanOrEqual(comparer(arrayA[offsetA], arrayA[offsetA - 1]), Comparison.EqualTo);
}
switch (comparer(arrayB[offsetB], arrayA[offsetA])) {
case Comparison.LessThan:
// If B is less than A, B does not exist in arrayA. Add B to the result and
// move to the next element in arrayB without changing the current position
// in arrayA.
result.push(arrayB[offsetB]);
continue loopB;
case Comparison.EqualTo:
// If B is equal to A, B exists in arrayA. Move to the next element in
// arrayB without adding B to the result or changing the current position
// in arrayA.
continue loopB;
case Comparison.GreaterThan:
// If B is greater than A, we need to keep looking for B in arrayA. Move to
// the next element in arrayA and recheck.
continue loopA;
}
}
}
return result;
}
export function sum<T extends Record<K, number>, K extends string>(array: readonly T[], prop: K): number {
let result = 0;
for (const v of array) {
result += v[prop];
}
return result;
}
/**
* Appends a value to an array, returning the array.
*
* @param to The array to which `value` is to be appended. If `to` is `undefined`, a new array
* is created if `value` was appended.
* @param value The value to append to the array. If `value` is `undefined`, nothing is
* appended.
*/
export function append<TArray extends any[] | undefined, TValue extends NonNullable<TArray>[number] | undefined>(to: TArray, value: TValue): [undefined, undefined] extends [TArray, TValue] ? TArray : NonNullable<TArray>[number][];
export function append<T>(to: T[], value: T | undefined): T[];
export function append<T>(to: T[] | undefined, value: T): T[];
export function append<T>(to: T[] | undefined, value: T | undefined): T[] | undefined;
export function append<T>(to: Push<T>, value: T | undefined): void;
export function append<T>(to: T[], value: T | undefined): T[] | undefined {
if (value === undefined) return to;
if (to === undefined) return [value];
to.push(value);
return to;
}
/**
* Combines two arrays, values, or undefineds into the smallest container that can accommodate the resulting set:
*
* ```
* undefined -> undefined -> undefined
* T -> undefined -> T
* T -> T -> T[]
* T[] -> undefined -> T[] (no-op)
* T[] -> T -> T[] (append)
* T[] -> T[] -> T[] (concatenate)
* ```
*/
export function combine<T>(xs: T | readonly T[] | undefined, ys: T | readonly T[] | undefined): T | readonly T[] | undefined;
export function combine<T>(xs: T | T[] | undefined, ys: T | T[] | undefined): T | T[] | undefined;
export function combine<T>(xs: T | T[] | undefined, ys: T | T[] | undefined) {
if (xs === undefined) return ys;
if (ys === undefined) return xs;
if (isArray(xs)) return isArray(ys) ? concatenate(xs, ys) : append(xs, ys);
if (isArray(ys)) return append(ys, xs);
return [xs, ys];
}
/**
* Gets the actual offset into an array for a relative offset. Negative offsets indicate a
* position offset from the end of the array.
*/
function toOffset(array: readonly any[], offset: number) {
return offset < 0 ? array.length + offset : offset;
}
/**
* Appends a range of value to an array, returning the array.
*
* @param to The array to which `value` is to be appended. If `to` is `undefined`, a new array
* is created if `value` was appended.
* @param from The values to append to the array. If `from` is `undefined`, nothing is
* appended. If an element of `from` is `undefined`, that element is not appended.
* @param start The offset in `from` at which to start copying values.
* @param end The offset in `from` at which to stop copying values (non-inclusive).
*/
export function addRange<T>(to: T[], from: readonly T[] | undefined, start?: number, end?: number): T[];
export function addRange<T>(to: T[] | undefined, from: readonly T[] | undefined, start?: number, end?: number): T[] | undefined;
export function addRange<T>(to: T[] | undefined, from: readonly T[] | undefined, start?: number, end?: number): T[] | undefined {
if (from === undefined || from.length === 0) return to;
if (to === undefined) return from.slice(start, end);
start = start === undefined ? 0 : toOffset(from, start);
end = end === undefined ? from.length : toOffset(from, end);
for (let i = start; i < end && i < from.length; i++) {
if (from[i] !== undefined) {
to.push(from[i]);
}
}
return to;
}