Interview Question

What is optional chaining?

Optional chaining safely short-circuits on null or undefined.

💡 Concept ✅ Quick Revision ⚡ JavaScript

Answer

Optional chaining stops a property access or call when its base value is null or undefined. • The `?.` operator returns undefined for the short-circuited chain. • It does not suppress errors from an undeclared root identifier. • Grouping can end the continuous optional chain.

Example

Code

const user = {};
console.log(user.address?.city);

Output

undefined

Quick Revision

Optional chaining safely short-circuits on null or undefined.

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