/*!
 * This module defines the ListDictionary class, a data structure
 * that combines a linked list and a dictionary.
 *
 * Author: Jan Curn (jan@apify.com)
 * Copyright(c) 2015 Apify. All rights reserved.
 *
 */
import type { LinkedListNode } from './linked_list.js';
/**
 * The main ListDictionary class.
 */
export declare class ListDictionary<T = unknown> {
    private linkedList;
    dictionary: Record<string, LinkedListNode<T>>;
    /**
     * Gets the number of item in the list.
     */
    length(): number;
    /**
     * Adds an item to the list. If there is already an item with same key, the function
     * returns false and doesn't make any changes. Otherwise, it returns true.
     */
    add(key: string, item: T, toFirstPosition?: boolean): boolean;
    /**
     * Gets the first item in the list. The function returns null if the list is empty.
     */
    getFirst(): T | null;
    /**
     * Gets the last item in the list. The function returns null if the list is empty.
     */
    getLast(): T | null;
    /**
     * Gets the first item from the list and moves it to the end of the list.
     * The function returns null if the queue is empty.
     */
    moveFirstToEnd(): T | null;
    /**
     * Removes the first item from the list.
     * The function returns the item or null if the list is empty.
     */
    removeFirst(): T | null;
    /**
     * Removes the last item from the list.
     * The function returns the item or null if the list is empty.
     */
    removeLast(): T | null;
    /**
     * Removes an item identified by a key. The function returns the
     * object if it was found or null if it wasn't.
     */
    remove(key: string): T | null;
    /**
     * Finds a request based on the URL.
     */
    get(key: string): T | null;
    /**
     * Removes all items from the list.
     */
    clear(): void;
}