​

function cloneDeep(obj) {

    if (typeof obj !== 'object' || obj === null) return obj;

    let cloned, i;

    if (obj instanceof Date) {

        cloned = new Date(obj.getTime());

        return cloned;

    }

    if (obj instanceof Array) {

        let l;

        cloned = [];

        for (i = 0, l = obj.length; i < l; i++) cloned[i] = cloneDeep(obj[i]);

        return cloned;

    }

    cloned = {};

    for (i in obj) if (obj.hasOwnProperty(i)) cloned[i] = cloneDeep(obj[i]);

    return cloned;

}