public T this[int index]
{
get
{
if (index < 0 || index >= Count)
{
throw new IndexOutOfRangeException();
}
WeightedAvlNode <T> current = root;
while (true)
{
int leftWeight = current.Left.Weight;
if (index < leftWeight)
{
current = current.Left;
}
else if (index > leftWeight)
{
index -= leftWeight + 1;
current = current.Right;
}
else
{
return(current.Payload);
}
}
}
}
public Descent Descend()
{
int leftWeight = _current.Left.Weight;
if (_index < leftWeight)
{
_current = _current.Left;
return(Descent.Left);
}
else if (_index > leftWeight)
{
_index -= leftWeight + 1;
_current = _current.Right;
return(Descent.Right);
}
else
{
return(Descent.Found);
}
}
public Descent Descend()
{
if (_current.IsNil)
{
return(Descent.Found);
}
else
{
if (_position <= _current.Left.Weight)
{
_current = _current.Left;
return(Descent.Left);
}
else
{
_position -= _current.Left.Weight + 1;
_current = _current.Right;
return(Descent.Right);
}
}
}
private PersistentList(WeightedAvlNode <T> root) : base(root)
{
}
public NodeLocator(int index, WeightedAvlNode <T> root)
{
_index = index;
_current = root;
}
public InsertionPointLocator(int position, WeightedAvlNode <T> root)
{
_position = position;
_current = root;
}