Aliases with JavaScript Destructuring
Destructuring in JavaScript has totally changed the way JavaScript is written these days; code is more concise to write but but, from a visual standpoint, the syntax of the language has changed so much. Any good developer knows, however, that change is the constant we live in.
The basic idea behind destructuring in object literals is as follows:
const obj = { x: 1 };
// Grabs obj.x as { x }
const { x } = obj;
There are cases where you want the destructured variable to have a different name than the property name; in that case, you'll use a : newName to specify a name for the variable:
// Grabs obj.x as as { otherName }
const { x: otherName } = obj;
The syntax for specifying an alternate destructured name for an object property is simple and needed. Destructuring had the capability to confuse developers, especially array destructuring and function argument destructuring, but this alias syntax is a simple trick to keep in your locker!
![9 Mind-Blowing WebGL Demos]()
As much as developers now loathe Flash, we're still playing a bit of catch up to natively duplicate the animation capabilities that Adobe's old technology provided us. Of course we have canvas, an awesome technology, one which I highlighted 9 mind-blowing demos. Another technology available...
![Camera and Video Control with HTML5]()
Client-side APIs on mobile and desktop devices are quickly providing the same APIs. Of course our mobile devices got access to some of these APIs first, but those APIs are slowly making their way to the desktop. One of those APIs is the getUserMedia API...
![Telephone Link Protocol]()
We've always been able to create links with protocols other than the usual HTTP, like mailto, skype, irc ,and more; they're an excellent convenience to visitors. With mobile phone browsers having become infinitely more usable, we can now extend that convenience to phone numbers:
The tel...
![Flexbox Equal Height Columns]()
Flexbox was supposed to be the pot of gold at the long, long rainbow of insufficient CSS layout techniques. And the only disappointment I've experienced with flexbox is that browser vendors took so long to implement it. I can't also claim to have pushed flexbox's limits, but...
Always have to check your site first to see any updates. Love it david. That’s where good developers stand out. Always adapting to new changes. Just trying to get hang of destructing as i’m not the smartest one in the room.
Hello. I’m using an alias for my destructed object property. How can I handle the property when it’s undefined?
Thanks.
I was looking for something like this. I wonder why the proposal for this feature didn’t follow the syntax of import statements.
Example:
const { x as otherName } = obj;this is the typescript syntax
I don’t know why people call it an “alias”. If it were an alias, changing the variable would change the object property. E.g.
let obj = { x: 1 } let { x: x_notalias } = obj x_notalias = 2 // 2 obj // { x: 1 }I think the only time you can have an alias in JavaScript is with reference types.
let obj = { x: 1 } let obj_alias = obj obj_alias.x = 2 obj // { x: 2 }When destructuring we use the word “alias” to refer to a differently named variable with the same value, rather than a different name that should reference the same variable.