i = 0, len = numberlist.length; i < len; i++) { console.log(i); //->1,2,3,4 } const numberlist = [1,2,3,4]; for (let item of numberlist) console.log(item); //->1,2,3,4 } let data_str = “͍͋͏͓͑"; for(let item of data_str) { console.log(item);//->͋ ͍ ͏ ͑ ͓ } for for of