Mastering TypeScript for Modern Web Development

TypeScript has become the standard for serious web development. If you're still writing plain JavaScript for production apps, you're leaving safety and productivity on the table.

Why TypeScript?

TypeScript adds static typing to JavaScript. This means:

Essential Patterns

Discriminated Unions

type ApiResponse<T> = 
  | { status: 'success'; data: T }
  | { status: 'error'; error: string }
  | { status: 'loading' };

function handleResponse<T>(response: ApiResponse<T>) {
  switch (response.status) {
    case 'success':
      return response.data; // TypeScript knows data exists
    case 'error':
      throw new Error(response.error); // TypeScript knows error exists
    case 'loading':
      return null;
  }
}

Generic Constraints

interface HasId {
  id: string | number;
}

function findById<T extends HasId>(items: T[], id: T['id']): T | undefined {
  return items.find(item => item.id === id);
}

Advanced Tips

The Path Forward

TypeScript is an investment that pays for itself. Start with strict mode enabled and never look back.