ts-best-practices

Type narrowing in TypeScript works by using discriminated unions and type guards to refine types within conditional blocks. This mechanism prevents runtime type errors by ensuring operations only execute on verified types.

The best way to handle API boundaries in TypeScript is to prefer unknown over any and use schema validation or type guards. This ensures safer handling of external data and reduces nulls and unknowns.

Perform exhaustiveness checks in TypeScript by applying discriminated unions to complex domain models. This pattern enforces explicit type handling and ensures all possible cases are evaluated during code review scenarios.

Use unknown over any in TypeScript code reviews to enforce explicit type handling and safer casts. Unknown requires type narrowing or validation before use, strengthening contracts across modules and preventing runtime errors.

Audit a TypeScript file for unsafe casts by checking for any type usage and explicit type assertions. Add proper type guards and discriminated unions to enforce type narrowing and achieve stronger type safety.