/// <summary>
/// Detaches the node's tail, clears the node's value, and releases the node to the pool.
///
/// Note: Nodes should generally not be released one at a time as it will incur much greater overhead than batching releases using LinkedHeadTail<T>s.
/// </summary>
public void TrimAndDispose()
{
value = default(T);
lock (poolLock) {
next = pool;
pool = this;
}
}
/// <summary>
/// Returns a Slinq that enumerates the values contained in the list.
/// Ownership of the nodes contained in the list is transferred to the Slinq. When the Slinq is disposed, the nodes will be added to the
/// disposal queue.
/// </summary>
public Slinq <T, LinkedContext <T> > SlinqAndDispose()
{
var slinq = LinkedContext <T> .Slinq(this, true);
head = null;
tail = null;
count = 0;
return(slinq);
}
/// <summary>
/// Releases the head of the list to the node pool.
/// The list must be well formed when calling this method or the program will enter an invalid state, resulting in unspecified behaviour.
/// </summary>
public void Dispose()
{
if (head != null)
{
head.Dispose();
}
head = null;
tail = null;
count = 0;
}
/// <summary>
/// Adds the head of the list to the disposal queue.
/// The list must be well formed when calling this method or the program will enter an invalid state, resulting in unspecified behaviour.
/// </summary>
public void DisposeInBackground()
{
if (head != null)
{
head.DisposeInBackground();
}
head = null;
tail = null;
count = 0;
}
/// <summary>
/// Appends the specified value to the value list for the specified key. If the key was previously unmapped it is appended to the key
/// list.
/// Calling this method transfers ownership of the specified node and any linked nodes to the lookup.
/// </summary>
public void Add(K key, Linked <T> value)
{
LinkedHeadTail <T> values;
if (!dictionary.TryGetValue(key, out values))
{
keys.Append(key);
}
values.Append(value);
dictionary[key] = values;
}
/// <summary>
/// Adds the nodes in the list to the specified lookup using the specified key selector.
///
/// Ownership of the nodes contained in this list is transerred to the lookup.
/// </summary>
public Lookup <K, T> AddTo <K, P>(Lookup <K, T> lookup, DelegateFunc <T, P, K> selector, P parameter)
{
while (head != null)
{
var node = head;
head = head.next;
node.next = null;
lookup.Add(selector(node.value, parameter), node);
}
tail = null;
count = 0;
return(lookup);
}
/// <summary>
/// Adds the nodes in the list to the specified lookup using the specified key selector.
/// Ownership of the nodes contained in this list is transerred to the lookup.
/// </summary>
public Lookup <K, T> AddTo <K>(Lookup <K, T> lookup, Func <T, K> selector)
{
while (head != null)
{
var node = head;
head = head.next;
node.next = null;
lookup.Add(selector(node.value), node);
}
tail = null;
count = 0;
return(lookup);
}
/// <summary>
/// Appends a pooled node with with specified value to the end of the list.
/// </summary>
public void Append(T value)
{
var node = Linked <T> .Borrow(value);
if (head == null)
{
head = node;
}
else
{
tail.next = node;
}
tail = node;
++count;
}
/// <summary>
/// Appends the specified list to the end of this list.
/// This list and the specified list must be well formed when calling this method or the program will enter an invalid state, resulting in
/// unspecified behaviour.
/// Calling this method will invalidate the specified list and any variables containing its nodes.
/// </summary>
public void Append(LinkedHeadTail <T> other)
{
if (other.count == 0)
{
// noop
}
else if (head == null)
{
head = other.head;
tail = other.tail;
count = other.count;
}
else
{
tail.next = other.head;
tail = other.tail;
count += other.count;
}
}
/// <summary>
/// Traverses the node list that starts with this node, clears the value of each node, and releases the resulting node list to the pool.
/// </summary>
public void Dispose()
{
var dt = default(T);
value = dt;
var runner = this;
while (runner.next != null)
{
runner = runner.next;
runner.value = dt;
}
lock (poolLock) {
runner.next = pool;
pool = this;
}
}
/// <summary>
/// Returns a pooled list node with the specified value.
/// </summary>
public static Linked <T> Borrow(T value)
{
Linked <T> node;
lock (poolLock) {
if (pool == null)
{
node = new Linked <T>();
}
else
{
node = pool;
pool = pool.next;
node.next = null;
}
}
node.value = value;
return(node);
}
private static bool DetectResetLoop(Linked <T> head)
{
Linked <T> slow = head, prefFast = head, fast = head;
while (slow != null && fast?.next != null)
{
slow = slow.next;
prefFast = fast.next;
fast = prefFast.next;
if (slow == fast)
{
// remove loop
// prefFast.next = null;
Debug.Log("Detect Loop");
return(true);
}
}
return(false);
}
/// <summary>
/// Returns a list that starts with the specified node.
/// The constructor will traverse the node links to set the tail and count fields.
/// If the specified node is null, the resulting list will be empty.
/// </summary>
public LinkedHeadTail(Linked <T> head)
{
if (head == null)
{
this.head = null;
tail = null;
count = 0;
}
else
{
this.head = head;
tail = head;
count = 1;
while (tail.next != null)
{
tail = tail.next;
++count;
}
}
}
/// <summary>
/// Appends the specified node to the end of the list.
/// The node links will be traversed to determine the new tail and count.
/// If the specified node is null, the list will not be modified.
/// </summary>
public void Append(Linked <T> node)
{
if (node != null)
{
if (head == null)
{
head = node;
}
else
{
tail.next = node;
}
tail = node;
++count;
while (tail.next != null)
{
tail = tail.next;
++count;
}
}
}
/// <summary>
/// Sorts the lookup's keys using the specified comparison and ordering.
/// This method uses an introspective merge sort algorithm that will optimally sort rather than split lists with 3 or fewer nodes.
/// </summary>
public Lookup <K, T> SortKeys(Comparison <K> comparison, bool ascending)
{
keys = Linked.Sort(keys, comparison, ascending);
return(this);
}
/// <summary>
/// Returns a list containing a single node with the specified value.
/// </summary>
public LinkedHeadTail(T value) : this(Linked <T> .Borrow(value))
{
}