/**
 * @module utils
 * @summary Internal utility functions used by Pubst.
 */
/**
 * @summary Safe `hasOwnProperty` check.
 *
 * @param {Object} item - The object to check.
 * @param {string} key - The property name.
 * @returns {boolean} `true` if the object has the given own property.
 */
export function hasOwnProperty(item: Object, key: string): boolean;
/**
 * @summary Check if a value is `undefined`.
 *
 * @param {*} input - The value to check.
 * @returns {boolean} `true` if the value is `undefined`.
 */
export function isUndefined(input: any): boolean;
/**
 * @summary Check if a value is defined (not `undefined`).
 *
 * @param {*} input - The value to check.
 * @returns {boolean} `true` if the value is not `undefined`.
 */
export function isDefined(input: any): boolean;
/**
 * @summary Check if a value is not set (`null` or `undefined`).
 *
 * @param {*} item - The value to check.
 * @returns {boolean} `true` if the value is `null` or `undefined`.
 */
export function isNotSet(item: any): boolean;
/**
 * @summary Check if a value is set (not `null` and not `undefined`).
 *
 * @param {*} item - The value to check.
 * @returns {boolean} `true` if the value is neither `null` nor `undefined`.
 */
export function isSet(item: any): boolean;
/**
 * @summary Return a value, falling back to a default if the value is not set.
 *
 * @param {*} value - The value to return if set.
 * @param {*} def - The default to return if `value` is `null` or `undefined`.
 * @returns {*} The value if set, otherwise the default.
 */
export function valueOrDefault(value: any, def: any): any;