class-factories are good enough. as real-world example, google-puppeteer uses class-factories to promisify its constructors, which are easy-to-reason.
if the below Browser/Page classes were also "async", it would be difficult to debug their intent in real-world code -- are their instances supposed to act as promises or as data-objects? i imagine code-maintennance would be a nightmare. ```js // "await" puppeteer's Browser constructor // https://github.com/GoogleChrome/puppeteer/blob/v1.19.0/lib/Browser.js#L23 class Browser extends EventEmitter { constructor(connection, contextIds, ...) { ... } static async create(connection, contextIds, ...) { const browser = new Browser(connection, contextIds, ...); await connection.send(...); return browser; } } // https://github.com/GoogleChrome/puppeteer/blob/v1.19.0/lib/Launcher.js#L184 const browser = await Browser.create(connection, [], ...); // "await" puppeteer's Page constructor // https://github.com/GoogleChrome/puppeteer/blob/v1.19.0/lib/Page.js#L36 class Page extends EventEmitter { constructor(client, target, ...) { ... } static async create(client, target, ...) { const page = new Page(client, target, ...); await page._initialize(); ... return page; } } // https://github.com/kaizhu256/puppeteer-to-istanbul-example/blob/6b3f599f/screenshot.js#L317 page1 = await module.exports.Page.create(null, tmp); ``` On Tue, Aug 27, 2019 at 11:36 AM Claude Pache <[email protected]> wrote: > > > Le 26 août 2019 à 17:11, Dimitrian Nine <[email protected]> a > écrit : > > Class is just function constructor that return object > > > Although in JS a class is represented by the same object as its > constructor, I don’t think it is good to assimilate the concept of JS class > and JS constructor. Indeed, a class consists not only of its constructor, > but also of all its associated methods. This is what is suggested by the > syntax: > > ```js > class C { > /* definition of all methods, not only constructor */ > } > ``` > > From that perspective, I understand very well what would be an “async > constructor”; but an “async class” doesn’t make much sense. > > —Claude > _______________________________________________ > es-discuss mailing list > [email protected] > https://mail.mozilla.org/listinfo/es-discuss >
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