这段实现深拷贝的代码为什么会出错呢

Question

这段实现深拷贝的代码为什么会出错呢？
暂时没有考虑会传进去，null,正则对象等

function deepclone(target) {

            let Tclass = target.constructor
            let cloneObject = new Tclass;

            for (let key in target) {

                if (target.hasOwnProperty(key)) {
                    cloneObject[key] = deepclone(target[key])
                }

            }
            return cloneObject
        }

        let obj = {
            name: 'wc',

            age: 18,
            address: {
                city: 'bj'
            },
            arr: [1, 2, 3]
        }


        let newobj = deepclone(obj)
        console.log(newobj);

Answer 1

最后多次测试发现还是要加一个判断，不然会一直递归然后爆栈

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