SOURCE

let arr = [0, 1, 2, 3, 4, 5, 6, 7, 8, 9];
arr.fill("jspang", 2, 5);
console.log(arr);

let arr1 = ["jspang", "技术胖", "大胖逼逼叨"];

for (let item of arr1) {
  console.log(item);
}

let arr2 = ["jspang", "技术胖", "大胖逼逼叨"];
for (let index of arr2.keys()) {
  console.log(index);
}

let arr3 = ["jspang", "技术胖", "大胖逼逼叨"];
for (let [index, val] of arr3.entries()) {
  console.log(index + ":" + val);
}

let arr4 = ["jspang", "技术胖", "大胖逼逼叨"];
let list = arr4.entries();
console.log(list.next().value);
console.log(list.next().value);
console.log(list.next().value);