Leverage automatic array type guards, isolated declarations, and strict type safety features in your full-stack applications.
Inferred Type Predicates
TypeScript 5.5 automatically infers type predicate signatures for functions returning boolean filtering logic on arrays, removing verbose explicit type guards.
// TypeScript 5.5 auto-infers: (nums: (number | null)[]) => number[] const numbers = [1, 2, null, 4, undefined, 6]; const validNumbers = numbers.filter((x): x is number => x !== null && x !== undefined); console.log(validNumbers); // TypeScript knows type is number[]