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New ES2019 JavaScript features every developer should be excited about

Brian Neville-O'Neill on September 26, 2019

Written by Gbolahan Olagunju✏️ JavaScript has come a long way since its early days, with many new additions and features designed specifically to ...

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Ali Ilman • Sep 27 '19

Optional chaining is something I'm so delighted to see.
All of us have written obj.property && obj.property.anotherProperty, and it's a pain to the eyes when the properties are long.

Victor Cordeiro Costa • Sep 29 '19

I hate to be that guy, but I need to nitpick some details of this article. My intention is just to help!

This section...

String.trimStart and String.trimEn

should be this

String.trimStart and String.trimEnd

Am I right?

And regarding the Optional catch binding, is the structure of both codes really similar?

Take a look at the below code, the console.log() line will only be executed if the try block fail

try {
  const parsedJsonData = JSON.parse(obj);
} catch (error) {
  //the variable error has to be declared weather used or unused
  console.log(obj);
}

Now, take a look at the below code, which have the optional catch binding ... the console.log() will be executed whether the try block fails or not. Not only when it fail, like the previous version.

function getName () {
  let name = "Gbolahan Olagunju";
  try {
    name = obj.details.name
  } catch {}
  console.log(name);
}

I am thinking here... maybe the similar structure will be something like this...

function getName () {
  let name = "Gbolahan Olagunju";
  try {
    name = obj.details.name
  } catch {
    console.log(name);
  }
}

Am I right?

Thanks!

Great article, I personally love the optional chaining operator ?., this makes the code so much more readable. However, it is good to mention that we need to avoid calling it when it it is not necessary, otherwise we can have unnecessary performance issues and unclear code behaviors. 👍

Timothée Clain • Sep 27 '19

pipeline operator !! yay

Anshul Sanghi • Oct 1 '19

Wow, I am working on a project right now that could literally use all of these features on an extensive level. I’ve found ts-optichain for optional chaining very good for now but the rest, I would really love to see. Is there a way to use these features with babel maybe?

Samano Cedillo • Sep 26 '19

Buen post!

Gracias por el aporte.

Daniel Rodríguez Rivero • Sep 27 '19

Is this real life? or is just fanta-sea?
By the way, I don't see why would we need to add an empty catch block, it will be better to make it entirely optional.

Matei Adriel • Sep 29 '19

U should open a proposal or something, amazing idea

GWigWam • Sep 30 '19

Hey, small detail:

In the code for trimStart/trimEnd you misspell 'massage'. Also, the output of message.trimEnd(); would still have the spaces at the start (left) of the string right?