JS how to use object destructuring after definition

Question

Sorry I know this is really a dumb question, but I couldn't find the answer after a couple of rounds googling. Code looks like below:

let x = 0
// After some calculation I know the obj should be:
const obj = {'x': 1 }
// Then how to destructuring assigment at this line
{ x } = obj // this is incorrect
// But if I use: x = obj.x, ESLint warns me: [eslint] Use object destructuring. (prefer-destructuring)

console.log(x);

So my question is how to use destructuring assignment after x has been defined.

I don't see a problem, `const obj = {'x': 1}; const { x } = obj;` works fine. Could you show more code? — dhilt, Jul 13 '18 at 03:09
@dhilt I have defined `let x = 0` before destructuring assignment. Which is different to your sample code, yours is destructuring assign on x on the fly of definition. Thank you all the same! — LiuWenbin_NO., Jul 13 '18 at 03:17

score 0 · Answer 1 · answered Jul 13 '18 at 03:15

0

The initialization and destructing should happen in the same line. If you want to set an initial value, why not use default value assignment.

let { x = 0 } = obj

answered Jul 13 '18 at 03:15

Sushanth --

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My problem was I cannot know what the `obj` is when define `x`. Thanks. – LiuWenbin_NO. Jul 13 '18 at 03:18
@LiuWenbin_NO. you failed to mention that in your problem statement. Given your current question, this is a completely valid answer. – Patrick Roberts Jul 13 '18 at 15:08
@PatrickRoberts OK.. But I think I have said that '// After some calculation I know the obj should be:' – LiuWenbin_NO. Jul 13 '18 at 15:21

JS how to use object destructuring after definition

1 Answers1