Async/Await in Javascript

Introduced by ES7, async/await has grown to become a considerable development in the field of asynchronous programming. It provided the Javascript users with an ability to use synchronous coding clubbed with the access of resources asynchronously, so it doesn’t halt the main code sequence or thread. It sounds like a complicated process and this blog will detangle all your doubts regarding async/await.

Async functions are known to be an accurate mixture of generators and promises and are built on promises as well. Sounds tricky right? Let us guide you through its usage as well as its pros and cons.

The need for async/await

The first reason for async/await’s widespread acknowledgment is its ability to decrease the boilerplate surrounding promises. It is proven to handle the chaining limitation i.e. It fixes the chain problem in promises.

So, let’s go a little back and history and understand that promises were launched with a fundamental motive to solve problems raised by asynchronous programming, but it took us years to realize that promises bring their share of complexities and syntax issues as well and hence cannot be the only viable solution. Although they help users in solving the issue of Callback Hell, their complexities cannot be ignored altogether.

So, async functions were launched to provide users with lesser hassle by providing a better syntax and makes the code look synchronous while the code is actually asynchronous.

The keyword used to assign the async function is async and the await keyword is permitted within the async keyword. This keyword has proven to enable promises to be presented in a very synchronized and cleaner way, and enable asynchronous programming with minimal complications.

The pros of using async/await

As mentioned above, the first and foremost advantage of using async is its ability to provide us with synchronous style coding and that opens a plethora of other advantages of using async/await. Let us briefly go through some of the major pros of async/await

1. Code is easily readable

As discussed above, async/await provides users with better syntax and a much-synchronized process which makes the code look much simpler. It makes the code much more refined than it was in promises with callbacks or chaining. The difference is much more evident when we are dealing with complex codes because that is when hurdles with promises are most visible.

Additionally, async/await also provides native browser support and all renowned and mainstream browsers are fully compatible with async functions.

2. Use numerous async functions in a row

As async functions have an uncomplicated and simpler syntax, they can be chained quite easily. Also, async functions can contain as many numbers of await expressions used without any complications.

Talking about await expressions, they complete the job of making the promise functions behave as synchronous, they do so by suspending all execution until the given promise is accepted or rejected. So, the return value we get after using the await function is the resolved value of the await expression.

3. Simpler debugging process

To understand this in simpler terms, we should know that debugging, especially in the case of promises is a complicated process because the debuggers won’t be willing to get into an asynchronous code. But what async/await does is that it makes the code feel like a synchronous code and to the compiler that is much easier when it comes to debugging. Also, native support facilitates debugging in more ways than one.

Cons of using Async/await

When you browse the internet, you’ll find numerous articles comparing async/await’s functioning with that of promises and most of them always end up concluding that Async/await is a significant improvement to the world of asynchronous programming and there’s no doubt in that but what they miss out on are some of the major drawbacks of async/await.

Firstly, async/await is the syntactic sugar of promises and is a promise itself, so it cannot magically alter our programming style totally.

Let us proceed further to list some visible drawbacks of async/await, so our users can weigh its pros and cons before using it while programming.

1. Error Handling

An async function is set to show two basic results, either a resolved value or a rejected value, and error handling are not exactly easy for these cases. In a normal case, we can simply use .then() for error handling or can use  .catch() for some exceptional cases.

But in the case of async functions, we use the try…catch statement to detect errors. In the case of await function results, every rejected value is treated as an exception. But this approach has its flaws too, try...catch is designed to look for every exception and detect errors, but this might lead to the catching of errors that usually might not have been caught in promises and this is not exactly an advantage in coding. It becomes fatal to look for undefined errors.

 

2. Too Sequential

Although async functions appear synchronous but deep down they are built asynchronous and one must avoid being super sequential while using them.

Conclusion

There’s no doubt in the fact that async/await Is a considerable improvement in the world of asynchronous programming on Javascript and it is found to be extremely efficient in increasing code readability as well as helping in debugging the code.

But one must take notice of the fact that understanding, promise is the first key step towards efficiently using async/await as they are basically promises but just a syntactic sugar of them.

We hope this blog provides you with the much-needed information about the async/await function and helped you weigh the pros and cons of the same. To dig deep into Javascript and its features, you can always visit our website www.codedamn.com.