/*---------------------------------------------------------------------------------------------
 *  Copyright (c) Microsoft Corporation. All rights reserved.
 *  Licensed under the MIT License. See License.txt in the project root for license information.
 *--------------------------------------------------------------------------------------------*/

/**
 * An interface for a JavaScript object that
 * acts a dictionary. The keys are strings.
 */
export type IStringDictionary<V> = Record<string, V>;
/**
 * An interface for a JavaScript object that
 * acts a dictionary. The keys are numbers.
 */
export type INumberDictionary<V> = Record<number, V>;
/**
 * Groups the collection into a dictionary based on the provided
 * group function.
 */
export declare function groupBy<K extends string | number | symbol, V>(
	data: V[],
	groupFn: (element: V) => K,
): Record<K, V[]>;
export declare function diffSets<T>(
	before: Set<T>,
	after: Set<T>,
): {
	removed: T[];
	added: T[];
};
export declare function diffMaps<K, V>(
	before: Map<K, V>,
	after: Map<K, V>,
): {
	removed: V[];
	added: V[];
};
export declare class SetMap<K, V> {
	private map;
	add(key: K, value: V): void;
	delete(key: K, value: V): void;
	forEach(key: K, fn: (value: V) => void): void;
}