[JS deep destructuring] #JavaScript

deep_destructuring.js

// from https://developer.mozilla.org/fr/docs/Web/JavaScript/Reference/Op%C3%A9rateurs/Affecter_par_d%C3%A9composition
var metadata = {
    title: "Scratchpad",
    translations: [
       {
        locale: "de",
        localization_tags: [ ],
        last_edit: "2014-04-14T08:43:37",
        url: "/de/docs/Tools/Scratchpad",
        title: "JavaScript-Umgebung"
       }
    ],
    url: "/en-US/docs/Tools/Scratchpad"
};

var { title: englishTitle, translations: [{ title: localeTitle }] } = metadata;

console.log(englishTitle); // "Scratchpad"
console.log(localeTitle);  // "JavaScript-Umgebung"

// + in parameters with defaults
// https://wesbos.com/destructuring-default-values/
const person = { first: 'Wes', last: 'Bos' };
const { middle: middleName = 'Super Rad' } = person;
console.log(middleName); // 'Super Rad'


// with dynamic keys
> const key = 'a';
undefined
> const { [key]: value, ...rest } = { a: 1, b: 2, c: 3 };
undefined
> value
1
> rest
{ b: 2, c: 3 }
> const remove = (key, { [key]: _, ...result }) => result;
undefined
> remove('a', { a: 1, b: 2, c: 3 });
{ b: 2, c: 3 }