Accessing class member pointers

Accessing class member pointers

Suppose I have the following definition of List and Node:



template <class T>
class List {
public:
class Iterator;
class ConstIterator;
//Constructors and Destructors.
List() : head(NULL), tail(NULL), size(0) {}
List(const List& list);
~List();
//Methods
Iterator begin();
ConstIterator begin() const;
Iterator end();
ConstIterator end() const;
void insert(const T& data);
void insert(const T& data, const Iterator& iterator);
void remove(const Iterator& iterator);
int getSize() const;
Iterator find(const T& item);
ConstIterator find(const T& item) const;
void sort();
//Operators
List operator = (const List& list);
private:
class Node;
Node* head;
Node* tail;
int size;
};
template <class T>
class List<T>::Node
{
public:
//Constructors and destructors
Node(const T& _data, const Node* _next) : data(_data), next(_next) {}
~Node(); //Destructor
//Methods
//Operators
Node operator = (const Node& node);
private:
T data;
Node* next;
};



I'm writing a function to insert data into a list like this:



template<class T>
void List<T>::insert(const T& data)
{
Node newNode = new Node(data, NULL);
if (head == NULL)
{
head = &newNode;
tail = &newNode;
}
else
{
(*tail)->next = &newNode;
tail = &newNode;
}
size++;
}



However what I find strange is that if I swap (*tail)->next = &newNode; to
(*tail).next = &newNode; it still compiles. Why, and what is the correct
way of doing it?