Master advanced type patterns and best practices for enterprise-grade type safety and code maintainability.
Advanced TypeScript types enable precise modeling of complex data structures and relationships. This page explores patterns like conditional types, mapped types, type inference, and more with real-world examples.
Create reusable type structures with placeholders for specific types. Useful for functions, classes, and components.
function identity<T>(arg: T): T {
return arg;
}
type Box<T> = {
value: T;
}
Express relationships between types based on certain conditions. Often used with inference in conditional types.
type IsNumber<T> = T extends number ? true : false;
type MyExclude<T, U> = T extends U ? never : T;
Create new types by transforming structure or property types of existing types. Useful for readonly or required modifiers.
type Optional<T> = {
[P in keyof T]?: T[P];
};
type Readonly<T> = {
readonly [P in keyof T]: T[P];
};
Predefined type operations available in TypeScript's standard library for common use cases.
type Person = {
name: string;
age: number;
};
type PartialPerson = Partial<Person>;
type PickName = Pick<Person, "name">;
Infer complex type relationships using the infer keyword in conditional types for advanced type manipulation.
type ReturnType<T> = T extends (...args: any) => infer R ? R : any;
Create complex type transformations by combining conditional types with mapped types for array transformations.
type MyExtract<T, U> = T extends U ? T : never;
type Flatten<T> = T extends Array<infer U> ? U : T;
Prevent runtime errors through compile-time type validation and complex validation patterns.
Create self-documenting code that's easier to maintain and evolve over time.
Build reusable type patterns that can be used across multiple projects and teams.