JS ES6 Destructuring, assign entire object and destructure its properties at the same time

Question

I am trying to assign and destructure at the same time

a = {x: 1, y: 5}
let b, {x} = a

result:

b = undefined
x = 1

I want:

b = {x: 1, y: 5}
x = 1

Is there any way to achieve that ? When I try to assign with const

const c, {y} = a
      ^
Uncaught SyntaxError: Missing initializer in const declaration

`const b = a, {x} = a`? Although that doesn't *copy* the object. — VLAZ, Mar 24 '21 at 09:32
@RaviAshara that creates an implicit global `x` (which throws an error in strict mode) — adiga, Mar 24 '21 at 09:38
Assigning multiple variables in a single expression is confusing enough. Adding destructuring on top is even worse. You might like it, most of your colleagues won't. If I see something like that, I will immediately refactor it. Please, have mercy to others. — zhulien, Mar 24 '21 at 09:45
`const { b = a, x } = a;`Assign the default value `a` to `b`. — DecPK, Mar 24 '21 at 09:50

score 0 · Answer 1 · answered Mar 24 '21 at 09:43

0

You could wrap a in an object and destructure a with a renaming to b and take the nested x directly.

const
    a = { x: 1, y: 5 },
    { a: b, a: { x } } = { a };

console.log(b);
console.log(x);

answered Mar 24 '21 at 09:43

Nina Scholz

1 Answers1