/**
 * Partitions an array into equivalence classes, where the equality relation is defined by a callback
 *
 * The time complexity is O(n*m), where n is the number of items and n is the number of equivalence classes
 */
export declare function groupByEquivalence<T>(items: ReadonlyArray<T>, equals: (a: T, b: T) => boolean): ReadonlyArray<ReadonlyArray<T>>;