Docs: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Proxy The `Proxy` object enables you to create a proxy for another object, which can intercept and redefine fundamental operations for that object. Example: ```js const handler = { get(obj, prop) { return prop in obj ? obj[prop] : 37; } }; const p = new Proxy({}, handler); p.a = 1; p.b = undefined; console.log(p.a, p.b); // 1, undefined console.log('c' in p, p.c); // false, 37 ``` [VueUse](https://vueuse.org/) uses this for [useMagicKeys](https://vueuse.org/core/useMagicKeys/) to create dynamic properties: ```js const { Ctrl_A_B, space, alt_s /* ... */ } = useMagicKeys() ``` Here the `Ctrl_A_B` is split into `['Ctrl', 'A', 'B']`, the property name dynamically defines multiple keyboard keys to monitor for.