let fruits = new Set();

fruits.add('apple');
fruits.add('banana');
fruits.add('kiwi');
fruits.add('orange');
console.log(fruits.size); // 4
fruits.add('orange');
console.log(fruits.size); // 4

console.log(fruits.has('apple')); // true
fruits.delete('apple');
console.log(fruits.has('apple')); // false

fruits.forEach(fruit => {
  console.log(`I love eating ${fruit}!`);
});

// 'I love eating banana!'
// 'I love eating kiwi!'
// 'I love eating orange!'

 fruits.clear();
console.log(fruits.size); // 0