53 lines
1020 B
JavaScript
53 lines
1020 B
JavaScript
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/**
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* @packageDocumentation
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*
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* Return the last value from an (async)iterable.
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*
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* @example
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*
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* ```javascript
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* import last from 'it-last'
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*
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* // This can also be an iterator, generator, etc
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* const values = [0, 1, 2, 3, 4]
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*
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* const res = last(values)
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*
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* console.info(res) // 4
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* ```
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*
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* Async sources must be awaited:
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*
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* ```javascript
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* import last from 'it-last'
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*
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* const values = async function * () {
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* yield * [0, 1, 2, 3, 4]
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* }
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*
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* const res = await last(values())
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*
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* console.info(res) // 4
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* ```
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*/
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function isAsyncIterable(thing) {
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return thing[Symbol.asyncIterator] != null;
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}
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function last(source) {
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if (isAsyncIterable(source)) {
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return (async () => {
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let res;
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for await (const entry of source) {
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res = entry;
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}
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return res;
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})();
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}
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let res;
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for (const entry of source) {
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res = entry;
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}
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return res;
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}
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export default last;
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//# sourceMappingURL=index.js.map
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