js配列クローン方法のまとめ

ES5     
1.slice

let arr = [2,4,434,43]
let arr1= arr.slice()
arr[0] = 'a'
console.log(arr,arr1) // [ 2, 4, 434, 43 ]
console.log(arr1 === arr) // false
2.     

Array.prototype.clone = function(){
    let a=[];
    for(let i=0,l=this.length;i