SOURCE

function clone (arr) {
    let value 
    if(arr instanceof Array){
        value = []
        for(let i in arr){
            value.push(clone(arr[i]))
        }
        return value
    }else if(arr instanceof Object){
        value = {}
        for(let i in arr){
            value[i] = clone(arr[i])
        }
        return value
    }else{
        return arr
    }
}
let test = [[1],[[1,2,3],2],{name:1, value:2}]
// let test = [[],[],[]]
console.log(11111111111111111111)
console.log(clone(test));