TypeScript Tips for Productivity

Essential TypeScript tips to boost your productivity as a developer and write more maintainable code.

Type Inference

TypeScript is excellent at inferring types, but you can help it along:

// Let TypeScript infer the return type
function add(a: number, b: number) {
  return a + b; // TypeScript knows this returns number
}

// Explicit typing when needed
interface User {
  id: number;
  name: string;
  email: string;
}

const users: User[] = [];

Utility Types

Leverage TypeScript's built-in utility types:

interface Todo {
  id: number;
  title: string;
  completed: boolean;
}

// Make all properties optional
type PartialTodo = Partial<Todo>;

// Make all properties required
type RequiredTodo = Required<Todo>;

// Pick specific properties
type TodoPreview = Pick<Todo, 'id' | 'title'>;

// Omit specific properties
type TodoWithoutId = Omit<Todo, 'id'>;

Advanced Patterns

Discriminated Unions

interface Square {
  kind: 'square';
  size: number;
}

interface Rectangle {
  kind: 'rectangle';
  width: number;
  height: number;
}

type Shape = Square | Rectangle;

function area(shape: Shape): number {
  switch (shape.kind) {
    case 'square':
      return shape.size * shape.size;
    case 'rectangle':
      return shape.width * shape.height;
  }
}

Best Practices

1. Use strict mode - Enable all strict TypeScript options
2. Avoid any - Use unknown or specific types instead
3. Leverage interfaces - Prefer interfaces over type aliases for objects
4. Use const assertions - For literal types

Conclusion

TypeScript's powerful type system can significantly improve code quality and developer experience when used effectively.