| # Deep Clone | |
| **Task:** "Deep clone this object." | |
| ## Without Ponytail | |
| ```bash | |
| npm install lodash | |
| ``` | |
| ```js | |
| import { cloneDeep } from "lodash"; | |
| const copy = cloneDeep(original); | |
| ``` | |
| Or the classic hack: | |
| ```js | |
| // fragile: loses Date, undefined, Map, Set, circular refs, functions | |
| const copy = JSON.parse(JSON.stringify(original)); | |
| ``` | |
| ## With Ponytail | |
| ```js | |
| // ponytail: structuredClone does this | |
| const copy = structuredClone(original); | |
| ``` | |
| **1 dependency (or a fragile hack) → 1 built-in.** `structuredClone` handles `Date`, `Map`, `Set`, `ArrayBuffer`, `RegExp`, circular references, and more, everything `JSON.parse/stringify` silently drops. Available in every browser since 2022 and Node.js since v17. Pull lodash in when you need the rest of it, not for one function. | |