Deep clone an object with structuredClone
Copy nested objects, arrays, Maps, Sets and Dates without sharing references, using the built-in structuredClone.
- JavaScript
- GreenSnippets
- MIT
- Executed with Node.js 22
function deepClone(value) {
return structuredClone(value);
}Example / expected output
const copy = deepClone({ when: new Date(0), tags: new Set(["a"]) });
copy.tags.add("b"); // the original Set is unchangedHow it works
structuredClone is built into modern browsers and Node.js 17+. Unlike JSON.parse(JSON.stringify(x)), it keeps Date, Map, Set, BigInt and circular references intact. It cannot clone functions or class methods, and throws a DataCloneError if it meets one.
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