The unused destructuring in Javascript
technikhil314
Posted on June 17, 2021
I was just going through MDN and ECMA specs and trying out some cool little time saving tricks with destructuring in javascript.
Destructuring array based on index
let arr = [10, 20, 30, 40, 50];
let {0: first, 3: forth, ...rest} = arr;
console.log(first) // 10
console.log(forth) // 40
console.log(rest) // {1: 20, 2: 30, 4: 50}
Ignore some values from array at a particular position
const [a, , b] = [1, 2, 3];
console.log(a); // 1
console.log(b); // 3
Using dynamic key in destructuring
let ab = {
a: 10,
b: 20
};
let a = 'a';
let {[a]: aVal} = ab;
console.log(aVal) //10
You can even use function call, string template etc in the dynamic key
function getDynamicKey() {
return "a";
}
let ab = {
a: 10,
b: 20
};
let {[getDynamicKey()]: aVal} = ab;
console.log(aVal) //10
đź’– đź’Ş đź™… đźš©
technikhil314
Posted on June 17, 2021
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