| 1 | import { AsyncIterableX } from './asynciterablex';
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| 2 | import { toArray } from './toarray';
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| 3 | export class ScanRightAsyncIterable extends AsyncIterableX {
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| 4 | constructor(source, fn, seed) {
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| 5 | super();
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| 6 | this._source = source;
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| 7 | this._fn = fn;
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| 8 | this._hasSeed = seed.length === 1;
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| 9 | this._seed = seed[0];
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| 10 | }
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| 11 | async *[Symbol.asyncIterator]() {
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| 12 | let hasValue = false, acc = this._seed;
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| 13 | const source = await toArray(this._source);
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| 14 | for (let offset = source.length - 1; offset >= 0; offset--) {
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| 15 | const item = source[offset];
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| 16 | if (hasValue || (hasValue = this._hasSeed)) {
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| 17 | acc = await this._fn(acc, item, offset);
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| 18 | yield acc;
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| 19 | }
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| 20 | else {
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| 21 | acc = item;
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| 22 | hasValue = true;
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| 23 | }
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| 24 | }
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| 25 | }
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| 26 | }
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| 27 | export function scanRight(source, accumulator, ...seed) {
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| 28 | return new ScanRightAsyncIterable(source, accumulator, seed);
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| 29 | }
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| 30 |
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| 31 |
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