/**
 * @class Stack
 * @util
 */
declare class Stack {
    /**
     * The ordered collection of items held in the stack, where the last element is the top.
     */
    items: unknown[];
    /**
     * Initializes the stack with an optional pre-populated array of items.
     */
    constructor(initial?: unknown[]);
    /**
     * Add new item or items at the back of the stack.
     *
     * @param {*} items An item to add.
     */
    push(...items: unknown[]): void;
    /**
     * Remove the last element from the stack and returns it.
     *
     * @returns {*}
     */
    pop(): unknown;
    /**
     * Return the last element from the stack (without modification stack).
     *
     * @returns {*}
     */
    peek(): unknown;
    /**
     * Check if the stack is empty.
     *
     * @returns {boolean}
     */
    isEmpty(): boolean;
    /**
     * Return number of elements in the stack.
     *
     * @returns {number}
     */
    size(): number;
}
export default Stack;