JavaScript ES6 Sets 对象详解：创建、方法与遍历

let animals = new Set();

animals.add('🐷');
animals.add('🐼');
animals.add('🐢');
animals.add('🐿');
console.log(animals.size); // 4
animals.add('🐼');
console.log(animals.size); // 4

console.log(animals.has('🐷')); // true
animals.delete('🐷');
console.log(animals.has('🐷')); // false

animals.forEach(animal => {
 console.log(`Hey ${animal}!`);
});

// Hey 🐼!
// Hey 🐢!
// Hey 🐿!

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

let myAnimals = new Set(['🐷', '🐢', '🐷', '🐷']);

myAnimals.add(['🐨', '🐑']);
myAnimals.add({ name: 'Rud', type: '🐢' });
console.log(myAnimals.size); // 4

myAnimals.forEach(animal => {
 console.log(animal);
});


// 🐷
// 🐢
// ["🐨", "🐑"]
// Object { name: "Rud", type: "🐢" }

console.log('Only unique characters will be in this set.'.length); // 43

let sentence = new Set('Only unique characters will be in this set.');
console.log(sentence.size); // 18

let moreAnimals = new Set(['🐺', '🐴', '🐕', '🐇']);

for (let animal of moreAnimals) {
 console.log(`Howdy ${ animal }`);
}

// Howdy 🐺
// Howdy 🐴
// Howdy 🐕
// Howdy 🐇

let partyItems = new Set(['🍕', '🍾', '🎊']);
let items = partyItems.values();

console.log(items.next());
console.log(items.next());
console.log(items.next());
console.log(items.next().done);

// Object {
// done: false,
// value: "🍕"
// }

// Object {
// done: false,
// value: "🍾"
// }

// Object {
// done: false,
// value: "🎊"
// }

// true