28 lines
759 B
JavaScript
28 lines
759 B
JavaScript
'use strict';
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Object.defineProperty(exports, '__esModule', {
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value: true,
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});
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exports.promiseReduce = promiseReduce;
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var _isPromise = require('./isPromise.js');
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/**
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* Similar to Array.prototype.reduce(), however the reducing callback may return
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* a Promise, in which case reduction will continue after each promise resolves.
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*
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* If the callback does not return a Promise, then this function will also not
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* return a Promise.
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*/
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function promiseReduce(values, callbackFn, initialValue) {
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let accumulator = initialValue;
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for (const value of values) {
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accumulator = (0, _isPromise.isPromise)(accumulator)
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? accumulator.then((resolved) => callbackFn(resolved, value))
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: callbackFn(accumulator, value);
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}
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return accumulator;
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}
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