// ====================================================================================
// Interfaces
// ====================================================================================
#region IComparable
public int CompareTo(DoubleLink <T> other)
{
if (other == null)
{
return(-1);
}
return(Data.CompareTo(other.Data));
}
// Add last element
public void AddFirst(DoubleLink <T> link)
{
Debug.Assert(link != null);
if (link.IsLinked)
{
link.Unlink();
}
link.LinkBefore(First);
}
// Add first element
public void AddLast(DoubleLink <T> link)
{
Debug.Assert(link != null);
if (link.IsLinked)
{
link.Unlink();
}
link.LinkAfter(Last);
}
// Adds @link element to the list, with replacing the specified element.
// This is equivalent to calling the sequence: LinkBefore(Replace); replace.Unlink();
public void LinkReplace(DoubleLink <T> link, DoubleLink <T> replace)
{
Debug.Assert(link != null);
Debug.Assert(replace != null);
if (link == replace)
{
return;
}
link.LinkReplace(replace);
}
// Adds this element to a list, before the given element.
public void LinkBefore(DoubleLink <T> before)
{
Debug.Assert(before != null);
Previous = before.Previous;
before.Previous = this;
Next = before;
if (Previous != null)
{
Previous.Next = this;
}
}
// ====================================================================================
// Methods
// ====================================================================================
// Remove link from list
public void Unlink()
{
if (Next != null)
{
Next.Previous = Previous;
}
if (Previous != null)
{
Previous.Next = Next;
}
Next = Previous = null;
}
// Adds this element to the list, after the specified element
public void LinkAfter(DoubleLink <T> after)
{
Debug.Assert(after != null);
Next = after.Next;
after.Next = this;
Previous = after;
if (Next != null)
{
Next.Previous = this;
}
}
// Adds this element to the list, with replacing the specified element.
// This is equivalent to calling the sequence: LinkBefore(Replace); replace.Unlink();
public void LinkReplace(DoubleLink <T> replace)
{
Debug.Assert(replace != null);
var replacePrev = replace.Previous;
var replaceNext = replace.Next;
Previous = replacePrev;
Next = replaceNext;
if (Previous != null)
{
Previous.Next = this;
}
if (Next != null)
{
Next.Previous = this;
}
replacePrev = null;
replaceNext = null;
}
// Create link without connection to the list
public DoubleLink(T data, DoubleLink <T> next, DoubleLink <T> previous)
{
Data = data;
Next = next;
Previous = previous;
}
// Adds this element to the list, after the specified element
public void LinkAfter(DoubleLink <T> link, DoubleLink <T> after)
{
Debug.Assert(link != null);
Debug.Assert(after != null);
link.LinkAfter(after);
}
// Adds this element to a list, before the given element.
public void LinkBefore(DoubleLink <T> link, DoubleLink <T> before)
{
Debug.Assert(link != null);
Debug.Assert(before != null);
link.LinkBefore(before);
}
// Unlink @link from the list
public void Unlink(DoubleLink <T> link)
{
Debug.Assert(link != null);
link.Unlink();
}
public DoubleLinkedList()
{
First = Last = Root;
}
