การส่งออกซ้ำและไฟล์รวม

// src/models/index.ts (barrel)
export { User } from './user';
export { Product } from './product';
export { Order } from './order';

// Before barrel:
import { User } from '../models/user';
import { Product } from '../models/product';

// After barrel:
import { User, Product } from '../models';

// index.ts
export * from './utils';
export * from './helpers';
export * from './validators';

export { default as MyButton } from './Button';
export { Button as Btn } from './Button';

export type { User, UserRole } from './user.types';

// features/auth/index.ts
export { AuthProvider } from './AuthProvider';
export { useAuth } from './useAuth';
export type { AuthUser } from './types';

// src/index.ts
export * from './models';
export * from './services';
export * from './utils';