JavaScript · Language basics

destructuring

Unpacks arrays into positional names and objects into property names. Use a colon to rename and = for defaults.

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Syntax

const [a, b] = list; const { id } = user;

Example

Try it

const [first, second] = [10, 20];
const { id, role: title = "learner" } = { id: 7, role: "admin" };
console.log(first, second, id, title);

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