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type Brand<Name, Type> = Type & { _brand: Name };

type Celcius = Brand<'Celcius', number>;
type Fahrenheit = Brand<'Fahrenheit', number>;

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declare function convertCtoF(degree: Celcius): Fahrenheit;

declare const fiveC: Celcius;
declare const fiveF: Fahrenheit;

convertCtoF(fiveF); // error :)
// Argument of type 'Brand<"Fahrenheit", number>' is not assignable to parameter of type 'Brand<"Celcius", number>'.
//  Type 'Brand<"Fahrenheit", number>' is not assignable to type '{ _brand: "Celcius"; }'.
//    Types of property '_brand' are incompatible.
//      Type '"Fahrenheit"' is not assignable to type '"Celcius"'.

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type Brand<Name, Type> = Type & { _brand?: Name } // optional
  
type Celcius = Brand<'Celcius', number>;
type Fahrenheit = Brand<'Fahrenheit', number>;
  
const fiveC: Celcius = 5; // typechecked :)

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declare const _phantom: unique symbol;
export type NewType<Name, Type> = Type & { [_phantom]?: Name };
  
export type Celcius = NewType<'Celcius', number>;
export type Fahrenheit = NewType<'Fahrenheit', number>;

// ...etc

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interface ProductModel {
  id: number;
  name: string;
  price: number;
  tax: number
}

const getFinalPrice = (product: ProductModel) =>
  product.price + product.tax;

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interface ProductModel {
  id: number;
  name: string;
  price: number;
  tax: number
}

const productList: ProductModel[] = [
  { id: 100, name: 'deluxe', price: 28, tax: 2.5 },
  { id: 101, name: 'giftcard', price: 30, tax: 3 },

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const getFinalPrice = (product: ProductModel) =>
  product.price + product.tax;

const getProductById = (products: ProductModel[], id: number) =>
  products.find(product => product.id === id);

const product = getProductById(productList, 1);
const finalPrice = getFinalPrice(product); // <- ERROR
// Argument of type 'ProductModel | undefined' is not assignable to parameter of type 'ProductModel'.
//  Type 'undefined' is not assignable to type 'ProductModel'.

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/* Intersection type */
interface Goku {
  withKamehameha: boolean;
}
interface Bejita {
  sayKakarot: boolean;
}
type Gogeta = Goku & Bejita;

const gogeta: Gogeta = {

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/* Enum */
enum Status {
  Initial,
  Fetching,
  Done,
  Error
}

interface ProductStore {
  products: ProductModel[];

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export interface TimeSlot {
  deliveryId: number;
  from: string;
  to: string;
}

export interface DeliveryTimeResponse {
  date: string;
  slots: {
    DayTime: TimeSlot;