SOURCE

{
  for (let index of ['d', '3', 'rfrf'].keys()) {
    // console.log(index);
  }
  for (let [index,value] of ['d', '3', 'rfrf'].entries()) {
    // console.log(index,value);
  }
}
{
  // console.log([1,2,3,7,5].copyWithin(0,3));
}
{
  console.log([1,2,3,9,5,6].find(item=>{
    return item>3
  }));
  console.log([1,2,3,9,5,6].filter(item=>{
    return item>3
  }));
  console.log([1,2,3,9,5,6].findIndex(item=>{
    return item>3
  }));
}
{
  console.log([2,3,101].includes(101));
    console.log([2,3,101].indexOf(101));

}