DoublyLinkedListNode.swift

/*
 * The MIT License (MIT)
 *
 * Copyright (C) 2019, CosmicMind, Inc. <http://cosmicmind.com>.
 * All rights reserved.
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 * THE SOFTWARE.
 */

internal class DoublyLinkedListNode<Element>: CustomStringConvertible {
  /**
   :name:	next
   :description:	Points to the successor element in the DoublyLinkedList.
   - returns:	DoublyLinkedListNode<Element>?
   */
  internal var next: DoublyLinkedListNode<Element>?
  
  /**
   :name:	previous
   :description:	points to the predacessor element in the DoublyLinkedList.
   - returns:	DoublyLinkedListNode<Element>?
   */
  internal var previous: DoublyLinkedListNode<Element>?
  
  /**
   :name:	data
   :description:	Satellite data.
   - returns:	Element?
   */
  internal var element: Element?
  
  /**
   :name:	description
   :description:	Conforms to the Printable Protocol.
   - returns:	String
   */
  internal var description: String {
    return "\(String(describing: element))"
  }
  
  /**
   :name:	init
   :description:	Constructor.
   */
  internal init(next: DoublyLinkedListNode<Element>?, previous: DoublyLinkedListNode<Element>?, element: Element?) {
    self.next = next
    self.previous = previous
    self.element = element
  }
}