index.js
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	'use strict';
	const pLimit = require('p-limit');

	class EndError extends Error {
	constructor(value) {
	super();
	this.value = value;
	}
	}

	// The input can also be a promise, so we await it
	const testElement = async (element, tester) => tester(await element);

	// The input can also be a promise, so we `Promise.all()` them both
	const finder = async element => {
	const values = await Promise.all(element);
	if (values[1] === true) {
	throw new EndError(values[0]);
	}

	return false;
	};

	const pLocate = async (iterable, tester, options) => {
	options = {
	concurrency: Infinity,
	preserveOrder: true,
	...options
	};

	const limit = pLimit(options.concurrency);

	// Start all the promises concurrently with optional limit
	const items = [...iterable].map(element => [element, limit(testElement, element, tester)]);

	// Check the promises either serially or concurrently
	const checkLimit = pLimit(options.preserveOrder ? 1 : Infinity);

	try {
	await Promise.all(items.map(element => checkLimit(finder, element)));
	} catch (error) {
	if (error instanceof EndError) {
	return error.value;
	}

	throw error;
	}
	};

	module.exports = pLocate;