1/**
2 * Works with JavaScript `bigint` values.
3 *
4 * This module exposes the native `BigInt` constructor together with helpers for
5 * checking, arithmetic, comparison, range checks, safe parsing and conversions
6 * that return `Option`, integer square roots, aggregation, ordering,
7 * equivalence, reducers, and combiners.
8 *
9 * @since 2.0.0
10 */
11
12import * as Combiner from "./Combiner.ts"
13import * as Equ from "./Equivalence.ts"
14import { dual } from "./Function.ts"
15import * as Option from "./Option.ts"
16import * as order from "./Order.ts"
17import type { Ordering } from "./Ordering.ts"
18import * as predicate from "./Predicate.ts"
19import * as Reducer from "./Reducer.ts"
20
21/**
22 * Exposes the global bigint constructor for JavaScript bigint coercion.
23 *
24 * **When to use**
25 *
26 * Use to access native JavaScript bigint constructor coercion from the Effect
27 * module namespace.
28 *
29 * **Gotchas**
30 *
31 * This follows native `BigInt` coercion rules. It throws for invalid strings or
32 * non-integral numbers, and whitespace-only strings coerce to `0n`.
33 *
34 * @see {@link fromString} for parsing strings into an `Option`
35 * @see {@link fromNumber} for converting safe integers into an `Option`
36 *
37 * **Example** (Constructing bigints)
38 *
39 * ```ts import.meta.vitest
40 * import { BigInt } from "effect"
41 *
42 * BigInt.BigInt(123) // => 123n
43 * BigInt.BigInt("456") // => 456n
44 * ```
45 *
46 * @category constructors
47 * @since 4.0.0
48 */
49export const BigInt = globalThis.BigInt
50
51const bigint0 = BigInt(0)
52const bigint1 = BigInt(1)
53const bigint2 = BigInt(2)
54
55/**
56 * Checks whether a value is a `bigint`.
57 *
58 * **When to use**
59 *
60 * Use to validate unknown input and narrow it to `bigint`.
61 *
62 * **Example** (Checking for bigints)
63 *
64 * ```ts import.meta.vitest
65 * import { BigInt } from "effect"
66 *
67 * BigInt.isBigInt(1n) // => true
68 * BigInt.isBigInt(1) // => false
69 * ```
70 *
71 * @category guards
72 * @since 2.0.0
73 */
74export const isBigInt: (u: unknown) => u is bigint = predicate.isBigInt
75
76/**
77 * Provides an addition operation on `bigint`s.
78 *
79 * **When to use**
80 *
81 * Use when you need a binary addition function for piping or higher-order APIs
82 * instead of the infix addition operator.
83 *
84 * **Example** (Adding bigints)
85 *
86 * ```ts import.meta.vitest
87 * import { BigInt } from "effect"
88 *
89 * BigInt.sum(2n, 3n) // => 5n
90 * ```
91 *
92 * @see {@link sumAll} for summing an iterable of `bigint` values
93 *
94 * @category math
95 * @since 2.0.0
96 */
97export const sum: {
98 (that: bigint): (self: bigint) => bigint
99 (self: bigint, that: bigint): bigint
100} = dual(2, (self: bigint, that: bigint): bigint => self + that)
101
102/**
103 * Provides a multiplication operation on `bigint`s.
104 *
105 * **When to use**
106 *
107 * Use to multiply two `bigint` values.
108 *
109 * **Example** (Multiplying bigints)
110 *
111 * ```ts import.meta.vitest
112 * import { BigInt } from "effect"
113 *
114 * BigInt.multiply(2n, 3n) // => 6n
115 * ```
116 *
117 * @see {@link multiplyAll} for multiplying an iterable of `bigint` values
118 *
119 * @category math
120 * @since 2.0.0
121 */
122export const multiply: {
123 (that: bigint): (self: bigint) => bigint
124 (self: bigint, that: bigint): bigint
125} = dual(2, (self: bigint, that: bigint): bigint => self * that)
126
127/**
128 * Provides a subtraction operation on `bigint`s.
129 *
130 * **When to use**
131 *
132 * Use to subtract one `bigint` value from another.
133 *
134 * **Example** (Subtracting bigints)
135 *
136 * ```ts import.meta.vitest
137 * import { BigInt } from "effect"
138 *
139 * BigInt.subtract(2n, 3n) // => -1n
140 * ```
141 *
142 * @category math
143 * @since 2.0.0
144 */
145export const subtract: {
146 (that: bigint): (self: bigint) => bigint
147 (self: bigint, that: bigint): bigint
148} = dual(2, (self: bigint, that: bigint): bigint => self - that)
149
150/**
151 * Divides one `bigint` by another safely.
152 *
153 * **When to use**
154 *
155 * Use to divide `bigint` values while representing division by zero as
156 * `Option.none`.
157 *
158 * **Details**
159 *
160 * Uses JavaScript `bigint` division, so non-exact quotients are truncated
161 * toward zero. Returns `Option.none()` when the divisor is `0n`.
162 *
163 * **Example** (Dividing bigints safely)
164 *
165 * ```ts import.meta.vitest
166 * import { BigInt, Option } from "effect"
167 *
168 * BigInt.divide(6n, 3n) // => Option.some(2n)
169 * BigInt.divide(6n, 0n) // => Option.none()
170 * ```
171 *
172 * @see {@link divideUnsafe} for division that throws when the divisor is `0n`
173 * @see {@link remainder} for the JavaScript remainder operation
174 *
175 * @category math
176 * @since 2.0.0
177 */
178export const divide: {
179 (that: bigint): (self: bigint) => Option.Option<bigint>
180 (self: bigint, that: bigint): Option.Option<bigint>
181} = dual(
182 2,
183 (self: bigint, that: bigint): Option.Option<bigint> => that === bigint0 ? Option.none() : Option.some(self / that)
184)
185
186/**
187 * Divides one `bigint` by another, throwing if the divisor is zero.
188 *
189 * **When to use**
190 *
191 * Use to divide `bigint` values where the divisor is known to be non-zero and
192 * division by zero should be a thrown exception.
193 *
194 * **Details**
195 *
196 * Uses JavaScript `bigint` division, so non-exact quotients are truncated
197 * toward zero.
198 *
199 * **Gotchas**
200 *
201 * Throws a `RangeError` when the divisor is `0n`.
202 *
203 * **Example** (Dividing bigints unsafely)
204 *
205 * ```ts import.meta.vitest
206 * import { BigInt } from "effect"
207 *
208 * BigInt.divideUnsafe(6n, 3n) // => 2n
209 * BigInt.divideUnsafe(6n, 4n) // => 1n
210 * ```
211 *
212 * @see {@link divide} for division that returns `Option.none` when the divisor is `0n`
213 *
214 * @category math
215 * @since 4.0.0
216 */
217export const divideUnsafe: {
218 (that: bigint): (self: bigint) => bigint
219 (self: bigint, that: bigint): bigint
220} = dual(2, (self: bigint, that: bigint): bigint => self / that)
221
222/**
223 * Returns the result of adding `1n` to a `bigint`.
224 *
225 * **When to use**
226 *
227 * Use to increment a `bigint` counter by one.
228 *
229 * **Example** (Incrementing a bigint)
230 *
231 * ```ts import.meta.vitest
232 * import { BigInt } from "effect"
233 *
234 * BigInt.increment(2n) // => 3n
235 * ```
236 *
237 * @category math
238 * @since 2.0.0
239 */
240export const increment = (n: bigint): bigint => n + bigint1
241
242/**
243 * Returns the result of subtracting `1n` from a `bigint`.
244 *
245 * **When to use**
246 *
247 * Use to decrement a `bigint` counter by one.
248 *
249 * **Example** (Decrementing a bigint)
250 *
251 * ```ts import.meta.vitest
252 * import { BigInt } from "effect"
253 *
254 * BigInt.decrement(3n) // => 2n
255 * ```
256 *
257 * @category math
258 * @since 2.0.0
259 */
260export const decrement = (n: bigint): bigint => n - bigint1
261
262/**
263 * Provides an `Order` instance for `bigint` that allows comparing and sorting BigInt values.
264 *
265 * **When to use**
266 *
267 * Use when you need to sort or compare bigint values through APIs that accept
268 * an ordering instance.
269 *
270 * **Example** (Comparing bigints with Order)
271 *
272 * ```ts import.meta.vitest
273 * import { BigInt } from "effect"
274 *
275 * const a = 123n
276 * const b = 456n
277 * const c = 123n
278 *
279 * BigInt.Order(a, b) // => -1
280 * BigInt.Order(b, a) // => 1
281 * BigInt.Order(a, c) // => 0
282 * ```
283 *
284 * @category instances
285 * @since 2.0.0
286 */
287export const Order: order.Order<bigint> = order.BigInt
288
289/**
290 * Equivalence instance for bigints using strict equality (`===`).
291 *
292 * **When to use**
293 *
294 * Use when checking bigint equality through APIs that accept an equivalence
295 * relation.
296 *
297 * **Example** (Comparing bigints for equivalence)
298 *
299 * ```ts import.meta.vitest
300 * import { BigInt } from "effect"
301 *
302 * BigInt.Equivalence(1n, 1n) // => true
303 * BigInt.Equivalence(1n, 2n) // => false
304 * ```
305 *
306 * @category instances
307 * @since 2.0.0
308 */
309export const Equivalence: Equ.Equivalence<bigint> = Equ.BigInt
310
311/**
312 * Returns `true` if the first argument is less than the second, otherwise `false`.
313 *
314 * **When to use**
315 *
316 * Use to test whether one `bigint` is strictly less than another.
317 *
318 * **Example** (Checking less-than comparisons)
319 *
320 * ```ts import.meta.vitest
321 * import { BigInt } from "effect"
322 *
323 * BigInt.isLessThan(2n, 3n) // => true
324 * BigInt.isLessThan(3n, 3n) // => false
325 * BigInt.isLessThan(4n, 3n) // => false
326 * ```
327 *
328 * @category predicates
329 * @since 4.0.0
330 */
331export const isLessThan: {
332 (that: bigint): (self: bigint) => boolean
333 (self: bigint, that: bigint): boolean
334} = order.isLessThan(Order)
335
336/**
337 * Returns a function that checks if a given `bigint` is less than or equal to the provided one.
338 *
339 * **When to use**
340 *
341 * Use to test whether one `bigint` is less than or equal to another.
342 *
343 * **Example** (Checking less-than-or-equal comparisons)
344 *
345 * ```ts import.meta.vitest
346 * import { BigInt } from "effect"
347 *
348 * BigInt.isLessThanOrEqualTo(2n, 3n) // => true
349 * BigInt.isLessThanOrEqualTo(3n, 3n) // => true
350 * BigInt.isLessThanOrEqualTo(4n, 3n) // => false
351 * ```
352 *
353 * @category predicates
354 * @since 4.0.0
355 */
356export const isLessThanOrEqualTo: {
357 (that: bigint): (self: bigint) => boolean
358 (self: bigint, that: bigint): boolean
359} = order.isLessThanOrEqualTo(Order)
360
361/**
362 * Returns `true` if the first argument is greater than the second, otherwise `false`.
363 *
364 * **When to use**
365 *
366 * Use to test whether one `bigint` is strictly greater than another.
367 *
368 * **Example** (Checking greater-than comparisons)
369 *
370 * ```ts import.meta.vitest
371 * import { BigInt } from "effect"
372 *
373 * BigInt.isGreaterThan(2n, 3n) // => false
374 * BigInt.isGreaterThan(3n, 3n) // => false
375 * BigInt.isGreaterThan(4n, 3n) // => true
376 * ```
377 *
378 * @category predicates
379 * @since 4.0.0
380 */
381export const isGreaterThan: {
382 (that: bigint): (self: bigint) => boolean
383 (self: bigint, that: bigint): boolean
384} = order.isGreaterThan(Order)
385
386/**
387 * Returns a function that checks if a given `bigint` is greater than or equal to the provided one.
388 *
389 * **When to use**
390 *
391 * Use to test whether one `bigint` is greater than or equal to another.
392 *
393 * **Example** (Checking greater-than-or-equal comparisons)
394 *
395 * ```ts import.meta.vitest
396 * import { BigInt } from "effect"
397 *
398 * BigInt.isGreaterThanOrEqualTo(2n, 3n) // => false
399 * BigInt.isGreaterThanOrEqualTo(3n, 3n) // => true
400 * BigInt.isGreaterThanOrEqualTo(4n, 3n) // => true
401 * ```
402 *
403 * @category predicates
404 * @since 4.0.0
405 */
406export const isGreaterThanOrEqualTo: {
407 (that: bigint): (self: bigint) => boolean
408 (self: bigint, that: bigint): boolean
409} = order.isGreaterThanOrEqualTo(Order)
410
411/**
412 * Checks whether a `bigint` is between a `minimum` and `maximum` value (inclusive).
413 *
414 * **When to use**
415 *
416 * Use to test whether a `bigint` falls inside an inclusive range.
417 *
418 * **Example** (Checking whether a bigint is within bounds)
419 *
420 * ```ts import.meta.vitest
421 * import { BigInt } from "effect"
422 *
423 * const between = BigInt.between({ minimum: 0n, maximum: 5n })
424 *
425 * between(3n) // => true
426 * between(-1n) // => false
427 * between(6n) // => false
428 * ```
429 *
430 * @see {@link clamp} for forcing a `bigint` into an inclusive range
431 *
432 * @category predicates
433 * @since 2.0.0
434 */
435export const between: {
436 (options: {
437 minimum: bigint
438 maximum: bigint
439 }): (self: bigint) => boolean
440 (self: bigint, options: {
441 minimum: bigint
442 maximum: bigint
443 }): boolean
444} = order.isBetween(Order)
445
446/**
447 * Restricts the given `bigint` to be within the range specified by the `minimum` and `maximum` values.
448 *
449 * **When to use**
450 *
451 * Use to force a `bigint` into an inclusive range.
452 *
453 * **Details**
454 *
455 * If the `bigint` is less than the minimum, the function returns the minimum.
456 * If the `bigint` is greater than the maximum, the function returns the
457 * maximum. Otherwise, it returns the original `bigint`.
458 *
459 * **Example** (Clamping a bigint to bounds)
460 *
461 * ```ts import.meta.vitest
462 * import { BigInt } from "effect"
463 *
464 * const clamp = BigInt.clamp({ minimum: 1n, maximum: 5n })
465 *
466 * clamp(3n) // => 3n
467 * clamp(0n) // => 1n
468 * clamp(6n) // => 5n
469 * ```
470 *
471 * @see {@link between} for checking whether a `bigint` is already inside a range
472 *
473 * @category math
474 * @since 2.0.0
475 */
476export const clamp: {
477 (options: {
478 minimum: bigint
479 maximum: bigint
480 }): (self: bigint) => bigint
481 (self: bigint, options: {
482 minimum: bigint
483 maximum: bigint
484 }): bigint
485} = order.clamp(Order)
486
487/**
488 * Returns the minimum between two `bigint`s.
489 *
490 * **When to use**
491 *
492 * Use to select the smaller of two `bigint` values.
493 *
494 * **Example** (Finding the minimum bigint)
495 *
496 * ```ts import.meta.vitest
497 * import { BigInt } from "effect"
498 *
499 * BigInt.min(2n, 3n) // => 2n
500 * ```
501 *
502 * @see {@link max} for selecting the larger value
503 *
504 * @category math
505 * @since 2.0.0
506 */
507export const min: {
508 (that: bigint): (self: bigint) => bigint
509 (self: bigint, that: bigint): bigint
510} = order.min(Order)
511
512/**
513 * Returns the maximum between two `bigint`s.
514 *
515 * **When to use**
516 *
517 * Use to select the larger of two `bigint` values.
518 *
519 * **Example** (Finding the maximum bigint)
520 *
521 * ```ts import.meta.vitest
522 * import { BigInt } from "effect"
523 *
524 * BigInt.max(2n, 3n) // => 3n
525 * ```
526 *
527 * @see {@link min} for selecting the smaller value
528 *
529 * @category math
530 * @since 2.0.0
531 */
532export const max: {
533 (that: bigint): (self: bigint) => bigint
534 (self: bigint, that: bigint): bigint
535} = order.max(Order)
536
537/**
538 * Determines the sign of a given `bigint`.
539 *
540 * **When to use**
541 *
542 * Use to classify a `bigint` as negative, zero, or positive.
543 *
544 * **Example** (Determining bigint signs)
545 *
546 * ```ts import.meta.vitest
547 * import { BigInt } from "effect"
548 *
549 * BigInt.sign(-5n) // => -1
550 * BigInt.sign(0n) // => 0
551 * BigInt.sign(5n) // => 1
552 * ```
553 *
554 * @category math
555 * @since 2.0.0
556 */
557export const sign = (n: bigint): Ordering => order.BigInt(n, bigint0)
558
559/**
560 * Determines the absolute value of a given `bigint`.
561 *
562 * **When to use**
563 *
564 * Use to remove the sign from a `bigint` while preserving its magnitude.
565 *
566 * **Example** (Calculating absolute values)
567 *
568 * ```ts import.meta.vitest
569 * import { BigInt } from "effect"
570 *
571 * BigInt.abs(-5n) // => 5n
572 * BigInt.abs(0n) // => 0n
573 * BigInt.abs(5n) // => 5n
574 * ```
575 *
576 * @category math
577 * @since 2.0.0
578 */
579export const abs = (n: bigint): bigint => (n < bigint0 ? -n : n)
580
581/**
582 * Determines the greatest common divisor of two `bigint`s.
583 *
584 * **When to use**
585 *
586 * Use to compute the greatest common divisor of two integer values.
587 *
588 * **Example** (Calculating greatest common divisors)
589 *
590 * ```ts import.meta.vitest
591 * import { BigInt } from "effect"
592 *
593 * BigInt.gcd(2n, 3n) // => 1n
594 * BigInt.gcd(2n, 4n) // => 2n
595 * BigInt.gcd(16n, 24n) // => 8n
596 * ```
597 *
598 * @see {@link lcm} for computing the least common multiple
599 *
600 * @category math
601 * @since 2.0.0
602 */
603export const gcd: {
604 (that: bigint): (self: bigint) => bigint
605 (self: bigint, that: bigint): bigint
606} = dual(2, (self: bigint, that: bigint): bigint => {
607 while (that !== bigint0) {
608 const t = that
609 that = self % that
610 self = t
611 }
612 return abs(self)
613})
614
615/**
616 * Determines the least common multiple of two `bigint`s.
617 *
618 * **When to use**
619 *
620 * Use to compute the least common multiple of two integer values.
621 *
622 * **Example** (Calculating least common multiples)
623 *
624 * ```ts import.meta.vitest
625 * import { BigInt } from "effect"
626 *
627 * BigInt.lcm(2n, 3n) // => 6n
628 * BigInt.lcm(2n, 4n) // => 4n
629 * BigInt.lcm(16n, 24n) // => 48n
630 * ```
631 *
632 * @see {@link gcd} for computing the greatest common divisor
633 *
634 * @category math
635 * @since 2.0.0
636 */
637export const lcm: {
638 (that: bigint): (self: bigint) => bigint
639 (self: bigint, that: bigint): bigint
640} = dual(
641 2,
642 (self: bigint, that: bigint): bigint =>
643 self === bigint0 || that === bigint0 ? bigint0 : abs((self * that) / gcd(self, that))
644)
645
646/**
647 * Returns the integer square root of a non-negative `bigint`.
648 *
649 * **When to use**
650 *
651 * Use when you need to compute an integer square root for a `bigint` that has
652 * already been validated as non-negative, and you want negative input to throw
653 * instead of returning `Option.none`.
654 *
655 * **Details**
656 *
657 * For non-perfect squares, returns the largest `bigint` whose square is less
658 * than or equal to the input.
659 *
660 * **Gotchas**
661 *
662 * Throws a `RangeError` if the input is negative.
663 *
664 * **Example** (Calculating square roots unsafely)
665 *
666 * ```ts import.meta.vitest
667 * import { BigInt } from "effect"
668 *
669 * BigInt.sqrtUnsafe(4n) // => 2n
670 * BigInt.sqrtUnsafe(9n) // => 3n
671 * BigInt.sqrtUnsafe(16n) // => 4n
672 * ```
673 *
674 * @see {@link sqrt} for returning `Option.none` when the input is negative
675 *
676 * @category math
677 * @since 4.0.0
678 */
679export const sqrtUnsafe = (n: bigint): bigint => {
680 if (n < bigint0) {
681 throw new RangeError("Cannot take the square root of a negative number")
682 }
683 if (n < bigint2) {
684 return n
685 }
686 let x = n / bigint2
687 while (x * x > n) {
688 x = ((n / x) + x) / bigint2
689 }
690 return x
691}
692
693/**
694 * Computes the integer square root of a `bigint` safely.
695 *
696 * **When to use**
697 *
698 * Use to compute an integer square root while representing negative input as
699 * `Option.none`.
700 *
701 * **Details**
702 *
703 * For non-perfect squares, returns the largest `bigint` whose square is less
704 * than or equal to the input. Returns `Option.none()` when the input is
705 * negative.
706 *
707 * **Example** (Calculating square roots safely)
708 *
709 * ```ts import.meta.vitest
710 * import { BigInt, Option } from "effect"
711 *
712 * BigInt.sqrt(4n) // => Option.some(2n)
713 * BigInt.sqrt(9n) // => Option.some(3n)
714 * BigInt.sqrt(16n) // => Option.some(4n)
715 * BigInt.sqrt(-1n) // => Option.none()
716 * ```
717 *
718 * @see {@link sqrtUnsafe} for square root computation that throws on negative input
719 *
720 * @category math
721 * @since 2.0.0
722 */
723export const sqrt = (n: bigint): Option.Option<bigint> =>
724 isGreaterThanOrEqualTo(n, bigint0) ? Option.some(sqrtUnsafe(n)) : Option.none()
725
726/**
727 * Takes an `Iterable` of `bigint`s and returns their sum as a single `bigint`. Returns `0n` for an empty iterable.
728 *
729 * **When to use**
730 *
731 * Use when you want an immediate aggregate from an iterable instead of a
732 * folding reducer owned by another API.
733 *
734 * **Example** (Summing iterable bigints)
735 *
736 * ```ts import.meta.vitest
737 * import { BigInt } from "effect"
738 *
739 * BigInt.sumAll([2n, 3n, 4n]) // => 9n
740 * ```
741 *
742 * @see {@link sum} for adding two `bigint` values
743 * @see {@link ReducerSum} for summing through APIs that consume a `Reducer`
744 *
745 * @category math
746 * @since 2.0.0
747 */
748export const sumAll = (collection: Iterable<bigint>): bigint => {
749 let out = bigint0
750 for (const n of collection) {
751 out += n
752 }
753 return out
754}
755
756/**
757 * Takes an `Iterable` of `bigint`s and returns their product as a single `bigint`. Returns `1n` for an empty iterable.
758 *
759 * **When to use**
760 *
761 * Use to multiply all `bigint` values in an iterable.
762 *
763 * **Example** (Multiplying iterable bigints)
764 *
765 * ```ts import.meta.vitest
766 * import { BigInt } from "effect"
767 *
768 * BigInt.multiplyAll([2n, 3n, 4n]) // => 24n
769 * ```
770 *
771 * @see {@link multiply} for multiplying two `bigint` values
772 * @see {@link ReducerMultiply} for multiplying through APIs that consume a `Reducer`
773 *
774 * @category math
775 * @since 2.0.0
776 */
777export const multiplyAll = (collection: Iterable<bigint>): bigint => {
778 let out = bigint1
779 for (const n of collection) {
780 if (n === bigint0) {
781 return bigint0
782 }
783 out *= n
784 }
785 return out
786}
787
788/**
789 * Converts a `bigint` to a `number` safely.
790 *
791 * **When to use**
792 *
793 * Use to convert a `bigint` to a JavaScript number only when it is a safe
794 * integer.
795 *
796 * **Details**
797 *
798 * If the `bigint` is outside the safe integer range for JavaScript (`Number.MAX_SAFE_INTEGER`
799 * and `Number.MIN_SAFE_INTEGER`), it returns `Option.none()`.
800 *
801 * **Example** (Converting bigints to numbers)
802 *
803 * ```ts import.meta.vitest
804 * import { BigInt as BI, Option } from "effect"
805 *
806 * BI.toNumber(42n) // => Option.some(42)
807 * BI.toNumber(9007199254740992n) // => Option.none()
808 * BI.toNumber(-9007199254740992n) // => Option.none()
809 * ```
810 *
811 * @see {@link fromNumber} for converting a safe integer number to `bigint`
812 *
813 * @category converting
814 * @since 2.0.0
815 */
816export const toNumber = (b: bigint): Option.Option<number> => {
817 if (b > BigInt(Number.MAX_SAFE_INTEGER) || b < BigInt(Number.MIN_SAFE_INTEGER)) {
818 return Option.none()
819 }
820 return Option.some(Number(b))
821}
822
823/**
824 * Parses a string into a `bigint` safely.
825 *
826 * **When to use**
827 *
828 * Use to parse a string as a `bigint` without throwing on invalid input.
829 *
830 * **Details**
831 *
832 * If the string is empty or contains characters that cannot be converted into a
833 * `bigint`, it returns `Option.none()`.
834 *
835 * **Example** (Parsing strings as bigints)
836 *
837 * ```ts import.meta.vitest
838 * import { BigInt, Option } from "effect"
839 *
840 * BigInt.fromString("42") // => Option.some(42n)
841 * BigInt.fromString(" ") // => Option.none()
842 * BigInt.fromString("a") // => Option.none()
843 * ```
844 *
845 * @see {@link BigInt} for native constructor coercion that throws on invalid input
846 *
847 * @category converting
848 * @since 2.4.12
849 */
850export const fromString = (s: string): Option.Option<bigint> => {
851 try {
852 return s.trim() === ""
853 ? Option.none()
854 : Option.some(BigInt(s))
855 } catch {
856 return Option.none()
857 }
858}
859
860/**
861 * Converts a number to a `bigint`.
862 *
863 * **When to use**
864 *
865 * Use to convert a JavaScript number to `bigint` only when it is a safe integer.
866 *
867 * **Details**
868 *
869 * If the number is outside the safe integer range for JavaScript
870 * (`Number.MAX_SAFE_INTEGER` and `Number.MIN_SAFE_INTEGER`) or if the number is
871 * not a valid `bigint`, it returns `Option.none()`.
872 *
873 * **Example** (Converting numbers to bigints)
874 *
875 * ```ts import.meta.vitest
876 * import { BigInt, Option } from "effect"
877 *
878 * BigInt.fromNumber(42) // => Option.some(42n)
879 * BigInt.fromNumber(Number.MAX_SAFE_INTEGER + 1) // => Option.none()
880 * BigInt.fromNumber(Number.MIN_SAFE_INTEGER - 1) // => Option.none()
881 * ```
882 *
883 * @see {@link toNumber} for converting `bigint` values back to safe integer numbers
884 * @see {@link BigInt} for native constructor coercion
885 *
886 * @category converting
887 * @since 2.4.12
888 */
889export function fromNumber(n: number): Option.Option<bigint> {
890 if (n > Number.MAX_SAFE_INTEGER || n < Number.MIN_SAFE_INTEGER) {
891 return Option.none()
892 }
893
894 try {
895 return Option.some(BigInt(n))
896 } catch {
897 return Option.none()
898 }
899}
900
901/**
902 * Returns the JavaScript remainder of dividing one `bigint` by another.
903 *
904 * **When to use**
905 *
906 * Use when you want native remainder semantics, including signed remainders and
907 * a thrown division-by-zero error.
908 *
909 * **Gotchas**
910 *
911 * Throws a `RangeError` when the divisor is `0n`.
912 *
913 * **Example** (Calculating remainders)
914 *
915 * ```ts import.meta.vitest
916 * import { BigInt } from "effect"
917 *
918 * BigInt.remainder(10n, 3n) // => 1n
919 * BigInt.remainder(15n, 4n) // => 3n
920 * ```
921 *
922 * @see {@link divide} for quotient calculation with division-by-zero represented as `Option.none`
923 *
924 * @category math
925 * @since 4.0.0
926 */
927export const remainder: {
928 (divisor: bigint): (self: bigint) => bigint
929 (self: bigint, divisor: bigint): bigint
930} = dual(2, (self: bigint, divisor: bigint): bigint => self % divisor)
931
932/**
933 * Reducer for combining `bigint`s using addition.
934 *
935 * **When to use**
936 *
937 * Use to sum many `bigint` values through APIs that consume a `Reducer`.
938 *
939 * **Details**
940 *
941 * The initial value is `0n`, so `combineAll([])` returns `0n`.
942 *
943 * @see {@link sumAll} for summing an iterable directly
944 * @see {@link ReducerMultiply} for multiplying `bigint` values
945 *
946 * @category math
947 * @since 4.0.0
948 */
949export const ReducerSum: Reducer.Reducer<bigint> = Reducer.make((a, b) => a + b, bigint0)
950
951/**
952 * Reducer for combining `bigint`s using multiplication.
953 *
954 * **When to use**
955 *
956 * Use to multiply many `bigint` values through APIs that consume a `Reducer`.
957 *
958 * **Details**
959 *
960 * The initial value is `1n`, so `combineAll([])` returns `1n`.
961 *
962 * @see {@link multiplyAll} for multiplying an iterable directly
963 * @see {@link ReducerSum} for summing `bigint` values
964 *
965 * @category math
966 * @since 4.0.0
967 */
968export const ReducerMultiply: Reducer.Reducer<bigint> = Reducer.make((a, b) => a * b, bigint1, (collection) => {
969 let acc = bigint1
970 for (const n of collection) {
971 if (n === bigint0) return bigint0
972 acc *= n
973 }
974 return acc
975})
976
977/**
978 * Combiner that returns the maximum `bigint`.
979 *
980 * **When to use**
981 *
982 * Use to keep the largest `bigint` when an API consumes a `Combiner`.
983 *
984 * @see {@link CombinerMin} for keeping the smallest `bigint`
985 * @see {@link max} for comparing two `bigint` values directly
986 *
987 * @category math
988 * @since 4.0.0
989 */
990export const CombinerMax: Combiner.Combiner<bigint> = Combiner.max(Order)
991
992/**
993 * Combiner that returns the minimum `bigint`.
994 *
995 * **When to use**
996 *
997 * Use to keep the smallest `bigint` through APIs that consume a `Combiner`.
998 *
999 * @see {@link CombinerMax} for keeping the largest `bigint`
1000 * @see {@link min} for comparing two `bigint` values directly
1001 *
1002 * @category math
1003 * @since 4.0.0
1004 */
1005export const CombinerMin: Combiner.Combiner<bigint> = Combiner.min(Order)