Does JavaScript have classes?

A friend and I had an argument last week. He stated there were no such things as classes in JavaScript. I said there was as you can say var object = new Object() He says "as there is no word class...

Combination of async function + await + setTimeout

I am trying to use the new async features and I hope solving my problem will help others in the future. This is my code which is working: async function asyncGenerator() { // other code ...

How to use ES8 async/await with streams?

In https://stackoverflow.com/a/18658613/779159 is an example of how to calculate the md5 of a file using the built-in crypto library and streams. var fs = require('fs'); var crypto =...

How to "await" for a callback to return?

When using a simple callback such as in the example below: test() { api.on( 'someEvent', function( response ) { return response; }); } How can the function be changed to use async /...

Using async/await with a forEach loop

Are there any issues with using async/await in a forEach loop? I'm trying to loop through an array of files and await on the contents of each file. import fs from 'fs-promise' async function...

Chain async functions

In an async function, I can get an asynchronous value like so: const foo = await myAsyncFunction() If I want to call a method on the result, with a sync function I'd do something like...

Use async await with Array.map

Given the following code: var arr = [1,2,3,4,5]; var results: number[] = await arr.map(async (item): Promise<number> => { await callAsynchronousOperation(item); return item + 1; ...

ES8 Immediately invoked async function expression

I haven't seen these constructs used much but I've found myself writing them to make use of async / await in functions that wouldn't typically return a promise, for example chan.consume(queue,...

try/catch blocks with async/await

I'm digging into the node 7 async/await feature and keep stumbling across code like this function getQuote() { let quote = "Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do...

How to await an asynchronous function?

My case: let waiting = function () { return new Promise(resolve => { console.log('awaiting...'); setTimeout(function () { resolve(); }, 1000) }); }; let waitingAsync =...

How to reject in async/await syntax?

How can I reject a promise that returned by an async/await function? e.g. Originally: foo(id: string): Promise<A> { return new Promise((resolve, reject) => { ...

Async/Await inside Array#map()

I'm getting compile time error with this code: const someFunction = async (myArray) => { return myArray.map(myValue => { return { id: "my_id", myValue: await...

Is async await truly non-blocking in the browser?

I have been playing around with the feature in an SPA using TypeScript and native Promises, and I notice that even if I refactor a long-running function into an async function returning a promise,...

async/await always returns promise

I'm trying async/await functionality. I have such code imitating a request: const getJSON = async () => { const request = () => new Promise((resolve, reject) => ( setTimeout(() => resolve({...

Is it possible to use await without async in Js

Await is a amazing feature in es7. However,everytime I use await I found that I have to define a async function and call this function. Such as async function asy(){ const...

When to mark function as async

Basically, function must be prefixed with async keyword if await used inside it. But if some function just returns Promise and doesn't awaiting for anything, should I mark the function as...

Correct Try...Catch Syntax Using Async/Await

I like the flatness of the new Async/Await feature available in Typescript, etc. However, I'm not sure I like the fact that I have to declare the variable I'm awaiting on the outside of a...

Property 'entries' does not exist on type 'ObjectConstructor'

I'm working on an ng2 implementation. I'm using the following function call to convert an object to an array: var authors = Object.entries(responseObject.Authors); This is a standard js...

What's the actual use of the Atomics object in ECMAScript?

The ECMAScript specification defines the Atomics object in the section 24.4. Among all the global objects this is the more obscure for me since I didn't know about its existence until I didn't...

How can I use async/await at the top level?

I have been going over async/await and after going over several articles, I decided to test things myself. However, I can't seem to wrap my head around why this does not work: async function...

Use Async/Await with Axios in React.js

Following How to use async/await with axios in react I am trying to make a simple get request to my server using Async/Await in a React.js App. The server loads a simple JSON at /data which looks...

Using await in then callback - the keyword 'await' is reserved

In node.js, I have a database transaction, where I want to call an async method in then callback, but I get error message the keyword 'await' is reserved. This is async saveImage function: const...

WebStorm 2019. Problem with connection of JavaScript debug mode

I have a next problem relation with as module JavaScript debug of WebStorm 2019. When I try to config my application into debug mode on my JavaScript modules, which have written on EcmaScript 6...

How to enable ES8 on WebStorm 2016

I have installed the WebStorm 2016, but in the options (File > Settings > Language & Frameworks) I see only a few JavaScript language versions, the last one is ECMAScript 6. Is there a way to add...

How does async-await work in JavaScript? Does making a function async make it asynchronous?

Does making a function async make it asynchronous? I started using async-await in place of a promise chain. I did something like async function f(){ let r = await first(); let d = await...

How to use async/await in Vue.js?

I'm new in ES7 I want to use async/await in Vue.js Here is my code created (){ this.getA() console.log(2) this.getB() }, methods : { getA (){ console.log(1) }, ...

How to install plugin-export-default-form to Babel in react project

I have been getting the following error constantly throughout this process SyntaxError: /Users/user1/npmprojects/experiments/test-reactstrap0/src/components/index.js: Support for the experimental...

ES7, ES8, ES9, ES10, ES11 Browser support

It is fairly easy to check out the data about browser support for ECMAScript2015 (ES6), but I found it pretty difficult to have an equivalently clear table for all the following ES versions (ES7...

Prettier, eslint - classProperties parser plugin error

I'm struggling to make my prettier works correctly. When I launch format-check (prettier --check on js,ts files) it gives me SyntaxError: This experimental syntax requires enabling the parser...

trying to 'npm install', getting node-gyp rebuild errors

I had to move my react-native code from another pc and when i tried to run npm install then this error will show. related answer : How can I solve error gypgyp ERR!ERR! find VSfind VS msvs_version...