1 | /**
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2 | * Returns the only element of an iterable sequence that matches the predicate if specified,
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3 | * or undefined if no such element exists; this method reports an exception if there is more
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4 | * than one element in the iterable sequence.
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5 | *
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6 | * @export
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7 | * @template T The type of the elements in the source sequence.
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8 | * @param {AsyncIterable<T>} source Source iterable sequence.
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9 | * @param {OptionalFindOptions<T>} [options] The optional options which includes a predicate for filtering,
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10 | * and thisArg for predicate binding.
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11 | * @returns {(T | undefined)} The single element in the iterable sequence that satisfies
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12 | * the condition in the predicate, or undefined if no such element exists.
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13 | */
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14 | export function single(source, options) {
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15 | const { ['thisArg']: thisArg, ['predicate']: predicate = () => true } = options || {};
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16 | let result;
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17 | let hasResult = false;
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18 | let i = 0;
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19 | for (const item of source) {
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20 | if (hasResult && predicate.call(thisArg, item, i++)) {
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21 | throw new Error('More than one element was found');
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22 | }
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23 | if (predicate.call(thisArg, item, i++)) {
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24 | result = item;
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25 | hasResult = true;
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26 | }
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27 | }
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28 | return result;
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29 | }
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30 |
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31 | //# sourceMappingURL=single.mjs.map
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