/**
 * Simple double linked list. Compared with array, it has O(1) remove operation.
 * @constructor
 * @alias clay.core.LinkedList
 */
export declare class Entry<T> {
    value: T;
    next?: Entry<T>;
    prev?: Entry<T>;
    constructor(val: T);
}
declare class LinkedList<T> {
    head?: Entry<T>;
    tail?: Entry<T>;
    private _length;
    constructor();
    /**
     * Insert a new value at the tail
     */
    insert(val: T): Entry<T>;
    /**
     * Insert a new value at idx
     * @param idx
     * @param val
     */
    insertAt(idx: number, val: T): void;
    insertBeforeEntry(val: T, next: Entry<T>): void;
    /**
     * Insert an entry at the tail
     * @param  entry
     */
    insertEntry(entry: Entry<T>): void;
    /**
     * Remove entry.
     * @param  entry
     */
    remove(entry: Entry<T>): void;
    /**
     * Remove entry at index.
     * @param  idx
     * @return
     */
    removeAt(idx: number): T | undefined;
    /**
     * Get head value
     * @return {}
     */
    getHead(): T | undefined;
    /**
     * Get tail value
     * @return {}
     */
    getTail(): T | undefined;
    /**
     * Get value at idx
     * @param idx
     * @return
     */
    getAt(idx: number): T | undefined;
    /**
     * @param  value
     */
    indexOf(value: T): number;
    /**
     * Length of list
     */
    length(): number;
    /**
     * If list is empty
     */
    isEmpty(): boolean;
    /**
     * @param  cb
     * @param  context
     */
    forEach(cb: (value: T, idx: number) => void): void;
    /**
     * Clear the list
     */
    clear(): void;
}
export default LinkedList;