Briefle words · Code & architecture
Nullish coalescing
Also called ??
An operator that supplies a default value when the one on its left is null or undefined.
Say it to an AI
React TSX ShippingCard for the order page. customer, shippingAddress and delivery are all optional, so handle them explicitly with optional chaining and nullish coalescing and show readable fallbacks like "Guest checkout" and "date TBC" rather than crashing.
How an expert would brief the stronger version of “Order shipping card”.
See it
Try it as a puzzle →Card on an online shop's admin order page. Guest orders have no customer; digital-only orders have no address or delivery.
Why: A's addr?.line1 ?? "No shipping address" shows a readable fallback instead of a blank or a crash.
Related words
Room 4 · Errors & edge cases
Learn “Nullish coalescing” in a five-minute lesson