Enhanced Type Safety for Modern JavaScript
TypeScript 5.5 introduces groundbreaking improvements in type inference, decorator support, and performance optimization. This release empowers developers to build safer, more maintainable applications with enhanced tooling and runtime efficiency.
Enhanced Type Inference
Intelligent contextual typing improves error detection by 45% with real-time expression analysis.
Decorator Enhancements
First-class decorator composition supports aspect-oriented programming patterns natively.
Performance Boost
35% faster type checking in large codebases with lazy evaluation of dependent types.
Tooling Integration
Seamless VS Code integration with instant error visualization in gutter decorations.
New Pattern Matching Feature
// Enhanced Discriminated Unions
function handleEvent(event: Event) {
switch (event.type) {
case "CLICK":
const clickEvent = event as typeof event.type === "CLICK" ? {
type: "CLICK",
button: "primary"
} : never;
console.log(clickEvent.button);
break;
case "HOVER":
// ...
}
}
TypeScript 5.5 Handbook
Comprehensive guide to new type safety features
Master advanced typing patterns, decorator composition, and performance optimization techniques with our interactive learning modules.
View Handbook