What does the following type guard pattern enable that ‘as’ casting does not? function isUser(value: unknown): value is User { return typeof value === ‘object’ && value !== null && ‘id’ in value; }
Key points
- Enables runtime-verified narrowing for type validation
- Integrates with TypeScript's type system for trust
- Ensures type checking reliability based on function return
- Combines actual validation with type system integration
Ready to go further?
