TypeScript中的接口和泛型你了解吗

type UserType = { name: string; age?: number };
const user: UserType = {
  name: "kiki",
  age: 18,
};
interface IUserType { name: string; age?: number }
const person: IUserType = {
  name: 'alice',
  age: 20
}

interface ILanguage {
  [index: number]: string;
}
const language: ILanguage = {
  0: "html",
  1: "CSS",
  2: "js",
};
type Score = {
  [name: string]: number;
}
const score: Score = {
  Chinese: 120,
  math: 95,
  Englist: 88,
};

interface ISelfType {
  (arg: string): string;
}
type LogType = (arg: string) => string;
function print(arg: string, fn: ISelfType, logFn: LogType) {
  fn(arg);
  logFn(arg);
}
function self(arg: string) {
  return arg;
}
console.log(print("hello", self, self));

interface ISwim {
  swimming: () => void;
}
interface IEat {
  eating: () => void;
}
interface IBird extends ISwim, IEat {}
const bird: IBird = {
  swimming() {},
  eating() {},
};

interface ISwim {
  swimming: () => void;
}
interface IEat {
  eating: () => void;
}
type Fish = ISwim | IEat;
type Bird = ISwim & IEat;
const fish: Fish = {
  swimming() {},
};
const bird: Bird = {
  swimming() {},
  eating() {},
};
export {}

interface ISwim {
  swimming: () => void
}
interface IEat {
  eating: () => void
}
class Animal {}
class Fish extends Animal implements ISwim, IEat {
  swimming(){}
  eating(){}
}
class Person implements ISwim {
  swimming(){}
}
function swiMaction(iswim: ISwim){
  iswim.swimming()
}
swimAction(new Fish())
swimAction(new Person())

enum Direction {
  LEFT,
  RIGHT,
  TOP,
  BOTTOM,
}
function turnDirection(direction: Direction) {
  switch (direction) {
    case Direction.LEFT:
      break;
    case Direction.RIGHT:
      break;
    case Direction.TOP:
      break;
    case Direction.BOTTOM:
      break;
    default:
      const foo: never = direction;
      break;
  }
}
turnDirection(Direction.LEFT);

function self<T>(element: T) {
  return element;
}
self<string>("alice");
self<number>(2);
self<null>(null);

function foo<T, E, O>(a: T, b: E, c: O){}
foo(1, 'alice', false)
foo(['alice'], undefined, null)

interface Person<T, E> {
  name: T;
  age: E;
}
const person: Person<string, number> = {
  name: "alice",
  age: 20,
};

interface Book<T = string, E = number> {
  cateGory: T;
  price: E;
}
const book: Book = {
  category: "nature",
  price: 88.6,
};
const dictionary: Book<number, string> = {
  category: 1,
  price: '88'
}

class Point<T> {
  x: T;
  y: T;
  z: T;
  constructor(x: T, y: T, z: T) {
    this.x = x;
    this.y = y;
    this.z = z;
  }
}
new Point("1.55", "2.34", "3.67");
new Point(1.55, 2.34, 3.67);

interface ILength {
  length: number;
}
function getLength<T extends ILength>(element: T) {
  return element.length;
}
getLength("alice");
getLength(["alice", "kiki", "lucy"]);
getLength({ length: 5 });