What is optional chaining in JavaScript?

Can you explain what optional chaining is in JavaScript?

Optional chaining is a feature in JavaScript that allows you to safely access deeply nested properties of an object without having to check if each reference in the chain is valid.

How does it work in practice?

You can use the ?. operator to access properties. For example, obj?.property will return undefined if obj is null or undefined, instead of throwing an error.

Can you give me an example?

Sure! If you have an object like const user = { profile: { name: 'Alice' } };, you can access the name with user.profile?.name, which returns 'Alice'. If profile was undefined, it would return undefined instead of an error.

What happens if I try to access a property that doesn't exist?

If you use optional chaining, it will simply return undefined instead of throwing an error. For example, user.profile?.age would return undefined if age doesn't exist.