public void Update(Func <TValue, TValue> transformer)
{
if (transformer == null)
{
throw new ArgumentNullException(nameof(transformer));
}
bool removedItem;
TValue newValue;
if (Key == null)
{
// If the Key is null then it means that this node is part of a chain but doesn't have its own Key and Value, in which case leave
// Value as whatever it currently is on the cloned node (should be default(T))
newValue = Value;
removedItem = false; // This node doesn't represent a value and so we haven't removed anything
}
else
{
newValue = transformer(Value);
removedItem = (newValue == null);
}
Key = removedItem ? null : Key;
Value = newValue;
LeftChild?.Update(transformer);
MiddleChild?.Update(transformer);
RightChild?.Update(transformer);
}
public Node Clone()
{
var newNode = new Node()
{
Character = Character,
LeftChild = LeftChild?.Clone(),
MiddleChild = MiddleChild?.Clone(),
RightChild = RightChild?.Clone(),
Parent = Parent,
Key = Key,
Value = Value
};
if (newNode.LeftChild != null)
{
newNode.LeftChild.Parent = newNode;
}
if (newNode.MiddleChild != null)
{
newNode.MiddleChild.Parent = newNode;
}
if (newNode.RightChild != null)
{
newNode.RightChild.Parent = newNode;
}
return(newNode);
}
/// <summary>
/// Returns a cloned copy of the node, deep-cloning all data. This will throw an exception for a null node.
/// </summary>
public Node Clone()
{
// To clone it, we copy Character, Parent, Key and Value onto a new instance and then clone the child nodes (if non-null). After this the
// Parents on the child nodes will have to be set to the new instance so that a new chain can be formed. This should be called against
// the root node such that an entirely new tree is formed.
var newNode = new Node()
{
Character = Character,
LeftChild = (LeftChild == null) ? null : LeftChild.Clone(),
MiddleChild = (MiddleChild == null) ? null : MiddleChild.Clone(),
RightChild = (RightChild == null) ? null : RightChild.Clone(),
Parent = Parent,
Key = Key,
Value = Value
};
if (newNode.LeftChild != null)
{
newNode.LeftChild.Parent = newNode;
}
if (newNode.MiddleChild != null)
{
newNode.MiddleChild.Parent = newNode;
}
if (newNode.RightChild != null)
{
newNode.RightChild.Parent = newNode;
}
return(newNode);
}
/// <summary>
/// Does the specified Node or any descendant have a true IsKey value? This will throw an exception for a null node.
/// </summary>
public bool ContainsAnyValues()
{
return(
(Key != null) ||
((LeftChild != null) && LeftChild.ContainsAnyValues()) ||
((MiddleChild != null) && MiddleChild.ContainsAnyValues()) ||
((RightChild != null) && RightChild.ContainsAnyValues())
);
}
