async method in class

async.method.in.class.js

async function foo(value) {
  // Return async result async
  return new Promise(resolve => {
    setTimeout(() => resolve(value), 100);
  });
}

class SuperClass {
  async getValue(value) {
    var result = await foo(value);
    return this.value + ' ' + result;
  }
}

class BaseClass extends SuperClass {
  constructor(value) {
    var asyncWrapperForSuper = async () => {
      super();
      this.value = await Promise.resolve('any-value');
    };
    asyncWrapperForSuper();
  }
}

const obj = new BaseClass();

obj.getValue('boo').then(result => console.log(result)); // any-value boo
obj.async(); // usual function