es6三点运算符

<script type="text/javascript">

    function func(a,b,...params){
        console.log(params);
        params.forEach(function(item,index){
            console.log(item,index);
        })
    }

    func(2,4,5,6);

    let arr1=[2,3];
    let arr2=[1,...arr1,4];
    console.log(arr2);
    console.log(...arr1);
</script>