| 1 | import { AsyncIterableX } from './asynciterablex';
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| 2 | export class DefaultIfEmptyAsyncIterable extends AsyncIterableX {
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| 3 | constructor(source, defaultValue) {
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| 4 | super();
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| 5 | this._source = source;
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| 6 | this._defaultValue = defaultValue;
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| 7 | }
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| 8 | async *[Symbol.asyncIterator]() {
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| 9 | let state = 1;
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| 10 | for await (let item of this._source) {
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| 11 | state = 2;
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| 12 | yield item;
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| 13 | }
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| 14 | if (state === 1) {
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| 15 | yield this._defaultValue;
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| 16 | }
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| 17 | }
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| 18 | }
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| 19 | export function defaultIfEmpty(source, defaultValue) {
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| 20 | return new DefaultIfEmptyAsyncIterable(source, defaultValue);
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| 21 | }
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| 22 |
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| 23 |
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