Back
Syntax
Study
Editor
Mode:
HTML
CSS
JavaScript
PHP
Reset
Run »
HTML / CSS / JS
const map = new Map(); map.set("key", 1); map.set({ id: 1 }, "obj key"); map.size; // 2 const set = new Set([1, 2, 2, 3]); // Set {1,2,3} set.has(2); // true const unique = [...new Set([1,1,2,3,3])]; // [1,2,3] // WeakMap/WeakSet — keys weakly held (GC-able) const cache = new WeakMap();
Result
Open