What are TypeScript utility types and how to use them

· Category: TypeScript

Short answer

TypeScript provides built-in utility types such as Partial<T>, Pick<T, K>, Omit<T, K>, and Record<K, T> to transform existing types without redeclaring them. For related type system guidance, see python type hints. For modular code organization, see python classes objects.

Steps

  1. Use Partial<User> to make all properties optional
  2. Use Pick<User, 'name' | 'email'> to select specific properties
  3. Use Omit<User, 'password'> to exclude properties
  4. Use Record<string, number> for dictionary-like objects
  5. Combine utilities for complex type transformations

Tips

  • Utility types reduce duplication and keep type definitions DRY
  • Create your own mapped types for project-specific patterns
  • For testing typed logic, consider python testing with pytest