type sortOptions<T> = {
    /**
     * Filter function to apply to the array before sorting
     * (default=isNotEmptyObject)
     */
    filter_fn?: (el: T) => boolean;
    /**
     * Remove objects that don't have the key or where the key is falsy
     * (default=false)
     */
    nokey_hide?: boolean;
    /**
     * Move invalid values (eg: non-objects or objects that don't match the key/function passed) to the end of the sorted array
     * (default=true)
     */
    nokey_atend?: boolean;
};
type sortByFunction = (el: Record<string, any>) => string;
/**
 * Sort an array of objects.
 *
 * The internals of this function swap between insertion and quicksort depending on the use-case.
 * Insertion sort is used for smaller arrays and quicksort is used for larger arrays.
 *
 * The threshold for insertion sort is 10 elements.
 *
 * The quicksort implementation is based on Tony Hoare's quicksort
 * (https://cs.stanford.edu/people/eroberts/courses/soco/projects/2008-09/tony-hoare/quicksort.html)
 *
 * Example:
 *  sort([
 *      {test: 'Peter'},
 *      {test: 'Jack'},
 *      {test: 'Pony'},
 *      {test: 'John'},
 *      {test: 'Joe'},
 *      {test: 'Bob'},
 *      {test: 'Alice'},
 *  ], 'test', 'desc');
 * Output:
 *  [{test: 'Pony'}, {test: 'Peter'}, {test: 'John'}, {test: 'Joe'}, {test: 'Jack'}, {test: 'Bob'}, {test: 'Alice'}]
 *
 * Example w/ Function:
 *  sort([
 *      {test: 'Peter'},
 *      {test: 'Pony'},
 *      {test: 'JOHn'},
 *      {test: 'Joe'},
 *  ], el => el.test.toLowerCase(), 'desc');
 * Output:
 *  [{test: 'Pony'}, {test: 'Peter'}, {test: 'JOHn'}, {test: 'Joe'}]
 *
 * @param {Array} val - Array to sort
 * @param {string|sortByFunction} by - Either a string (key) or a function
 * @param {'desc'|'asc'} dir - (default='asc') Direction to sort in (asc or desc)
 * @param {sortOptions} opts - Sort options
 * @throws {Error}
 */
declare function sort<T extends {
    [key: string]: any;
}>(arr: T[], by: string | sortByFunction, dir?: 'asc' | 'desc', opts?: sortOptions<T>): T[];
export { sort, sort as default };