/**
 * Copyright (c) Facebook, Inc. and its affiliates.
 *
 * This source code is licensed under the MIT license found in the
 * LICENSE file in the root directory of this source tree.
 *
 * Utility for traversing the dependency graph starting at some key.
 *
 * @emails oncall+recoil
 * @flow strict-local
 * @format
 */
'use strict';

import type { Graph } from '../core/Recoil_Graph';
import type { NodeKey } from '../core/Recoil_State';
type DepGraph = $PropertyType<Graph, 'nodeDeps'>;
type VisitInfo = $ReadOnly<{
  key: NodeKey,
  deps: $ReadOnlySet<NodeKey>,
}>;
type OnVisit = (VisitInfo) => ?StopTraversing;
opaque type StopTraversing = string;
declare function traverseDepGraph(depGraph: DepGraph, initialKeys: NodeKey[], onVisit: OnVisit): void;
traverseDepGraph.STOP_TRAVERSING = ('__stopTraversing': StopTraversing);
module.exports = traverseDepGraph;