JS Async: async/awaitPublished at
You can check out the other 2 previous articles:
Today we’ll talk about
async/await and see some examples of how and what we can do with it:
The keyword async was implemented in ES2017. It makes it possible to create naturally asynchronous functions using the following notation:
Something important and even more interesting about this implementation is that every
async function returns a Promise, meaning that we can use all the interfaces we already know in the article about promises. Let's look at an example to better understand:
async functions use the success values as the values that will be arranged within the
.then pipeline in the promise that will be returned, in case you need to export an error, it is necessary to trigger an error within the scope of execution to be sent to the
.catch pipeline, let's see an example:
The use of
await is restricted only within a function declared with the keyword async, basically what it does is wait for the Promise response value or convert the value into a resolved Promise.
In cases where we are not returning any value from our function, the execution call remains a normal function call without using
Catching errors with try/catch
Await always expects the success value of the promise, so we have no way to capture the error directly, to do this we have to make use of the
try/catch which receives the reject value if it happens, within the promises that are being executed inside the
Executing this block, the error happens inside the promise
myAsyncErrorFunction and is captured inside the try/catch
In summary, the joint use of the implementations makes our code extremely simple and readable, making handling asynchronous (or synchronous) data more direct and effective.
I hope you enjoyed this series, see you later!