Building with TypeScript

TypeScript brings static typing to JavaScript, making your code more reliable and maintainable.

Type Definitions

Here are some common TypeScript patterns:

typescript

// Interface for component props
interface UserCardProps {
  user: {
    id: number
    name: string
    email: string
    avatar?: string
  }
  onEdit?: (id: number) => void
  className?: string
}

// Generic utility type
type ApiResponse<T> = {
  data: T
  message: string
  success: boolean
}

// Union types for state
type LoadingState = 'idle' | 'pending' | 'success' | 'error'

// Utility types
type UserUpdate = Partial<Pick<User, 'name' | 'email'>>

Advanced Types

TypeScript offers powerful type manipulation:

typescript

// Conditional types
type NonNullable<T> = T extends null | undefined ? never : T

// Mapped types
type Optional<T> = {
  [P in keyof T]?: T[P]
}

// Template literal types
type EventName<T extends string> = `on${Capitalize<T>}`

// Example usage
type ButtonEvents = EventName<'click' | 'hover'> // 'onClick' | 'onHover'

Benefits

Catch errors early - Before runtime
Better IDE support - Autocomplete and refactoring
Self-documenting code - Types serve as documentation
Easier refactoring - Compiler helps catch breaking changes

Best Practices

Start with strict: true in tsconfig.json
Use interfaces for object shapes
Prefer type for unions and computed types
Avoid any when possible
Use utility types for common patterns

TypeScript is an investment that pays dividends in code quality and developer experience!