private ImHashMap(Data data, ImHashMap <K, V> left, ImHashMap <K, V> right, int height)
{
_data = data;
Left = left;
Right = right;
Height = height;
}
private ImHashMap(Data data, ImHashMap <K, V> left, ImHashMap <K, V> right)
{
_data = data;
Left = left;
Right = right;
Height = 1 + (left.Height > right.Height ? left.Height : right.Height);
}
private ImHashMap(Data data)
{
_data = data;
Left = Empty;
Right = Empty;
Height = 1;
}
/// <summary>Depth-first in-order traversal as described in http://en.wikipedia.org/wiki/Tree_traversal
/// The only difference is using fixed size array instead of stack for speed-up (~20% faster than stack).</summary>
/// <returns>Sequence of enumerated key value pairs.</returns>
public IEnumerable <KV <K, V> > Enumerate()
{
if (Height == 0)
{
yield break;
}
var parents = new ImHashMap <K, V> [Height];
var node = this;
var parentCount = -1;
while (node.Height != 0 || parentCount != -1)
{
if (node.Height != 0)
{
parents[++parentCount] = node;
node = node.Left;
}
else
{
node = parents[parentCount--];
yield return(new KV <K, V>(node.Key, node.Value));
if (node.Conflicts != null)
{
for (var i = 0; i < node.Conflicts.Length; i++)
{
yield return(node.Conflicts[i]);
}
}
node = node.Right;
}
}
}
internal ImHashMap <K, V> Remove(int hash, K key, bool ignoreKey = false)
{
if (Height == 0)
{
return(this);
}
ImHashMap <K, V> result;
if (hash == Hash) // found node
{
if (ignoreKey || Equals(Key, key))
{
if (!ignoreKey && Conflicts != null)
{
return(ReplaceRemovedWithConflicted());
}
if (Height == 1) // remove node
{
return(Empty);
}
if (Right.IsEmpty)
{
result = Left;
}
else if (Left.IsEmpty)
{
result = Right;
}
else
{
// we have two children, so remove the next highest node and replace this node with it.
var successor = Right;
while (!successor.Left.IsEmpty)
{
successor = successor.Left;
}
result = new ImHashMap <K, V>(successor._data,
Left, Right.Remove(successor.Hash, default(K), ignoreKey: true));
}
}
else if (Conflicts != null)
{
return(TryRemoveConflicted(key));
}
else
{
return(this); // if key is not matching and no conflicts to lookup - just return
}
}
else if (hash < Hash)
{
result = new ImHashMap <K, V>(_data, Left.Remove(hash, key, ignoreKey), Right);
}
else
{
result = new ImHashMap <K, V>(_data, Left, Right.Remove(hash, key, ignoreKey));
}
if (result.Height == 1)
{
return(result);
}
return(result.KeepBalance());
}
private ImHashMap <K, V> With(ImHashMap <K, V> left, ImHashMap <K, V> right)
{
return(left == Left && right == Right ? this : new ImHashMap <K, V>(_data, left, right));
}