/**
 * Represents a collection which is bidirectional.
 *
 * @template TParent
 * The type of the parent of the collection.
 *
 * @template TChild
 * The type of the children of the collection.
 */
export declare abstract class BidirectionalCollection<TParent, TChild> extends Array<TChild> {
    /**
     * The owner of the collection.
     */
    private owner;
    /**
     * Initializes a new instance of the {@link BidirectionalCollection `BidirectionalCollection<TParent, TChild>`} class.
     *
     * @param owner
     * The owner of the collection.
     */
    constructor(owner: TParent);
    /**
     * Gets the owner of the collection.
     */
    get Owner(): TParent;
    /**
     * @inheritdoc
     *
     * @param items
     * The new elements of the Array.
     *
     * @returns
     * The new length of the array.
     */
    push(...items: TChild[]): number;
    /**
     * @inheritdoc
     *
     * @returns
     * The removed item.
     */
    pop(): TChild;
    /**
     * @inheritdoc
     *
     * @returns
     * The removed element.
     */
    shift(): TChild;
    /**
     * @inheritdoc
     *
     * @param items
     * Elements to insert at the start of the array.
     *
     * @returns
     * The new length of the array.
     */
    unshift(...items: TChild[]): number;
    /**
     * Gets the parent of a child.
     *
     * @param child
     * The child whose parent to return.
     *
     * @returns
     * The parent of the {@link child `child`}.
     */
    protected abstract GetParent(child: TChild): TParent;
    /**
     * Sets the parent of a child.
     *
     * @param child
     * The child whose parent is to be set.
     *
     * @param parent
     * The parent to set.
     */
    protected abstract SetParent(child: TChild, parent: TParent): void;
    /**
     * Securely adds an item.
     *
     * @param item
     * The item to add.
     *
     * @returns
     * A value indicating whether the item could be added.
     */
    protected Add(item: TChild): boolean;
    /**
     * Securely removes an item.
     *
     * @param index
     * The index of the item to remove.
     *
     * @returns
     * A value indicating whether the element could be removed.
     */
    protected Remove(index: number): boolean;
}