1. Async is a utility module which provides straight-forward, powerful functions for working with asynchronous JavaScript. Although originally designed for use with Node.js and installable via npm install --save async, it can also be used directly in the browser.
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3. This version of the package is optimized for the Node.js environment. If you use Async with webpack, install async-es instead.
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5. For Documentation, visit https://caolan.github.io/async/
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7. For Async v1.5.x documentation, go HERE
8.  
9. // for use with Node-style callbacks...
10. var async = require("async");
11.  
12. var obj = {dev: "/dev.json", test: "/test.json", prod: "/prod.json"};
13. var configs = {};
14.  
15. async.forEachOf(obj, (value, key, callback) => {
16.     fs.readFile(__dirname + value, "utf8", (err, data) => {
17.         if (err) return callback(err);
18.         try {
19.             configs[key] = JSON.parse(data);
20.         } catch (e) {
21.             return callback(e);
22.         }
23.         callback();
24.     });
25. }, err => {
26.     if (err) console.error(err.message);
27.     // configs is now a map of JSON data
28.     doSomethingWith(configs);
29. });
30. var async = require("async");
31.  
32. // ...or ES2017 async functions
33. async.mapLimit(urls, 5, async function(url) {
34.     const response = await fetch(url)
35.     return response.body
36. }, (err, results) => {
37.     if (err) throw err
38.     // results is now an array of the response bodies
39.     console.log(results)
40. })
41. Keywords
42. asynccallbackmoduleutility
43. install
44. npm i async
45.  
46. weekly downloads
47. 21 717 381
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