const target = { name: 'Sarah', age: 25 };
const handler = {
  get(obj, prop) {
    if (prop === 'info') {
      return `${obj.name} is ${obj.age}`;
    }
    return Reflect.get(obj, prop);
  },
  has(obj, prop) {
    return prop !== 'age' && Reflect.has(obj, prop);
  }
};
const proxy = new Proxy(target, handler);
console.log(proxy.info);
console.log('age' in proxy);
console.log('name' in proxy);

console.log('1');

setTimeout(() => console.log('2'), 0);

Promise.resolve().then(() => console.log('3'));

queueMicrotask(() => console.log('4'));

setTimeout(() => {
  console.log('5');
  Promise.resolve().then(() => console.log('6'));
}, 0);

console.log('7');

const target = { name: 'Sarah', age: 25 };

const handler = {
  get(obj, prop) {
    if (prop in obj) {
      return obj[prop];
    }
    return `Property '${prop}' not found`;
  },
  set(obj, prop, value) {
    obj[prop] = value.toString().toUpperCase();
    return true;
  }
};

const proxy = new Proxy(target, handler);
proxy.city = 'boston';
console.log(proxy.name);
console.log(proxy.city);
console.log(proxy.country);

const Flyable = {
  fly() { return 'flying'; }
};

const Swimmable = {
  swim() { return 'swimming'; }
};

function applyMixins(target, ...mixins) {
  mixins.forEach(mixin => {
    Object.assign(target.prototype, mixin);
  });
}

class Bird {}
class Fish {}

applyMixins(Bird, Flyable, Swimmable);
applyMixins(Fish, Swimmable);

const eagle = new Bird();
const shark = new Fish();

console.log(eagle.swim());
console.log(shark.fly?.() || 'undefined method');