Mastering TypeScript: Advanced Types and Patterns

Advanced TypeScript Concepts

TypeScript's type system is incredibly powerful. In this guide, we'll explore advanced concepts that will make you a TypeScript expert.

Generic Types

Generics allow you to create reusable components that work with multiple types:

function identity<T>(arg: T): T {
  return arg;
}

let output = identity<string>("myString");
let output2 = identity<number>(100);

Conditional Types

Conditional types allow you to create types that depend on a condition:

type ApiResponse<T> = T extends string 
  ? { message: T } 
  : { data: T };

type StringResponse = ApiResponse<string>; // { message: string }
type NumberResponse = ApiResponse<number>; // { data: number }

Utility Types

TypeScript provides several utility types for common transformations:

interface User {
  id: number;
  name: string;
  email: string;
  password: string;
}

type PublicUser = Pick<User, 'id' | 'name' | 'email'>;
type UserWithoutPassword = Omit<User, 'password'>;
type PartialUser = Partial<User>;

Best Practices

• Use strict TypeScript configuration
• Prefer type inference when possible
• Use union types for flexible APIs
• Leverage utility types for transformations

Conclusion

Advanced TypeScript features enable you to build more robust applications. Master these concepts gradually and focus on solving real problems.