ecmascript-2017

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 / await? Specifically, assuming 'someEvent' is guaranteed to be called once and only once, I'd like the function test to be an async function which does not return until the callback is executed such as: async test() { return await api.on( 'someEvent' ); } async/await is not magic. An async function is a function that can unwrap Promises for you, so you'll need api.on() to return a Promise for that to work. Something

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 main() { var value = await Promise.resolve('Hey there'); console.log('inside: ' + value); return value; } var text = main(); console.log('outside: ' + text) The console outputs the following (node v8.6.0) : > outside: [object Promise] > inside: Hey there Why does the log message inside the function execute afterwards? I thought the reason async/await was created was in order to perform synchronous

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; }); which produces the following error: TS2322: Type 'Promise<number>[]' is not assignable to type 'number[]'. Type 'Promise<number> is not assignable to type 'number'. How can I fix it? How can I make async await and Array.map work together? Ajedi32 The problem here is that you are trying to await an array of promises rather than a promise. This doesn't do what you expect. When the object passed to await is not a

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 eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat. Duis aute irure dolor in reprehenderit in voluptate velit esse cillum dolore eu fugiat nulla pariatur. Excepteur sint occaecat cupidatat non proident, sunt in culpa qui officia deserunt mollit anim id est laborum."; return quote; } async