class 式

const Rectangle = class {
  constructor(height, width) {
    this.height = height;
    this.width = width;
  }
  area() {
    return this.height * this.width;
  }
};
console.log(new Rectangle(5, 8).area());
// 予想される結果: 40

class {
  // クラス本体
}
class name {
  // クラス本体
}

const Foo = class {
  constructor() {}
  bar() {
    return "Hello World!";
  }
};
const instance = new Foo();
instance.bar(); // "Hello World!"
Foo.name; // "Foo"

const Foo = class NamedFoo {
  constructor() {}
  whoIsThere() {
    return NamedFoo.name;
  }
};
const bar = new Foo();
bar.whoIsThere(); // "NamedFoo"
NamedFoo.name; // ReferenceError: NamedFoo is not defined
Foo.name; // "NamedFoo"