function deepCopy(obj, parent = null) {
	let result
	let _parent = parent
	while (_parent) {
		if (_parent.originalParent === obj) {
			return _parent.currentParent
		}
		_parent = _parent.parent
	}
	if (obj && typeof(obj) === 'object') {
		if (obj instanceof RegExp) {
			result = new RegExp(obj.source, obj.flags)
		} else if (obj instanceof Date) {
			result = new Date(obj.getTime())
		} else {
			if (obj instanceof Array) {
				result = []
			} else {
				let proto = Object.getPrototypeOf(obj)
				result = Object.create(proto)
			}
			for (let i in obj) {
				if (obj[i] && typeof(obj[i]) === 'object') {
					result[i] = deepCopy(obj[i], {
						originalParent: obj,
						currentParent: result,
						parent: parent
					})
				} else {
					result[i] = obj[i]
				}
			}
		}
	} else {
		return obj
	}
	return result
}
export default deepCopy