Promises Tutorials
![cookieStore: Async Cookie API]()
cookieStore: Async Cookie API
One pattern in the JavaScript API world that web development veterans will notice is that we've been creating new methods to accomplish what older, grosser APIs once achieved.
XMLHttpRequestbecame thefetchAPI, some APIs like Battery became async, and there are dozens of other examples.![How to Create an Async Function via “new Function”]()
How to Create an Async Function via “new Function”
One thing I love about JavaScript is that there are many ways to accomplish the same task, one such example being creating functions. There are several patterns for functions; one of the last you see used is the
new Functionmethod:What if you want...
![5 Awesome JavaScript Promise Tricks]()
5 Awesome JavaScript Promise Tricks
The Promise API changed the game in JavaScript. We went from abusing
setTimeouts and settling for synchronous operations to doing everything possible to leverage this new async API. Let's check out a handful of awesome Promise API tricks!Cancel a fetch RequestOne problem we...![Promise.allSettled]()
Promise.allSettled
The Promise object has many useful functions like
all,resolve,reject, andrace-- stuff we use all the time. One function that many don't know about isPromise.allSettled, a function that fires when all promises in an array are settled, regardless of whether...![How to Cancel a Fetch Request]()
How to Cancel a Fetch Request
JavaScript promises have always been a major win for the language -- they've led to a revolution of asynchronous coding that has vastly improved performance on the web. One shortcoming of native promises is that there's no true way to cancel a
fetch...until now. A...-
![JavaScript waitForTime]()
JavaScript waitForTime
I write a lot of tests for new features within Firefox DevTools. We have hundreds of "mochitests" which open the browser and perform synthetic actions like clicking, typing, and other user actions. I've previously written about
waitForeverwhich essentially halts following actions without locking the...![Promises and Static Values]()
Promises and Static Values
Async can throw a real wrench into the cogs of our programming workflows, all despite the fact that async is the modern JavaScript pattern. While async/await helps, there's sometimes confusion about the way to have a single function that returns a value whether it exists...
![then on Objects]()
then on Objects
Promises were a revelation in JavaScript development, allowing us to enjoy async processing and avoid callback hell. Many new APIs like Battery API, Cache API, and others use the promise API. One fact you may not know is that you can add...
![JavaScript Proxy with Storage]()
JavaScript Proxy with Storage
The JavaScript Proxy API provides a wealth of "magic" within JavaScript, allowing you to use any object as sort of an alias that allows a wall of validation, formatting, and error throwing. Did you know that you could also employ the Proxy API as...
![JavaScript Detect Async Function]()
JavaScript Detect Async Function
JavaScript async/await has changed the landscape of how we code. We're no longer stuck in callback or
thenhell, and our code can feel more "top down" again.Async functions require the following syntax:To useawaitwith a function, the function needs to be declared with...
