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/**
 * Represents a branded type for nominal typing in TypeScript.
 * Useful for distinguishing types that have the same underlying structure
 * but represent different concepts (e.g., UserId vs ProductId).
 */
type Brand<T, K> = T & { __brand: K };

// Example Usage:
type UserId = Brand<string, 'UserId'>;
type ProductId = Brand<string, 'ProductId'>;
type OrderId = Brand<string, 'OrderId'>;

function processUser(id: UserId) {
  console.log(`Processing user with ID: ${id}`);
}

function processProduct(id: ProductId) {
  console.log(`Processing product with ID: ${id}`);
}

const myUserId: UserId = 'user-123' as UserId;
const myProductId: ProductId = 'prod-abc' as ProductId;

processUser(myUserId); // OK
// processUser(myProductId); // Type Error: Argument of type 'ProductId' is not assignable to parameter of type 'UserId'.
console.log('--- Branded Types Demo ---');
console.log(`User ID: ${myUserId}`);
console.log(`Product ID: ${myProductId}`);

// If you try to assign directly without casting, TypeScript will treat them as strings:
const anotherUserId: UserId = 'user-456' as UserId; // Needs casting to ensure type safety
// const invalidUserId: UserId = 'prod-xyz' as ProductId; // Still a type error if you cast to the wrong brand