import { Params } from '../../types';
import { MusterEvent, NodeDefinition, NodeLike, StatefulGraphNode, StatefulNodeDefinition, StatefulNodeType } from '../../types/graph';
/**
 * An instance of the [[invalidateOn]] node.
 * See the [[invalidateOn]] documentation to find out more.
 */
export interface InvalidateOnNode extends StatefulGraphNode<'invalidate-on', InvalidateOnNodeProperties, InvalidateOnNodeState, InvalidateOnNodeData> {
}
/**
 * A definition of the [[invalidateOn]] node.
 * See the [[invalidateOn]] documentation to find out more.
 */
export interface InvalidateOnNodeDefinition extends StatefulNodeDefinition<'invalidate-on', InvalidateOnNodeProperties, InvalidateOnNodeState, InvalidateOnNodeData> {
}
export declare type InvalidateOnNodeCallback = (event: MusterEvent, props: Params) => NodeDefinition | undefined;
export interface InvalidateOnNodeProperties {
    target: NodeDefinition;
    predicate: (event: MusterEvent) => boolean;
}
export interface InvalidateOnNodeState {
}
export interface InvalidateOnNodeData {
    subscription: () => void;
}
/**
 * The implementation of the [[invalidateOn]].
 * See the [[invalidateOn]] to learn more.
 */
export declare const InvalidateOnNodeType: StatefulNodeType<'invalidate-on', InvalidateOnNodeProperties, InvalidateOnNodeState>;
export declare type AcceptedPredicateTypes = InvalidateOnNodeProperties['predicate'] | MusterEvent['type'] | Array<MusterEvent['type']>;
/**
 * Creates a new instance of an [[invalidateOn]] node, which is a type of [[NodeDefinition]] used to trigger
 * the invalidation mechanism. Invalidation causes the target node to lose its value and forces a re-fetch of it.
 * This is particularly useful for nodes like [[fromPromise]] or [[computed]] that can change the value depending on some
 * external factors e.g. calling an API endpoint or some local variable in the code (which is not recommended).
 *
 * It works similarly to the [[invalidate]] with the difference being the mechanism triggering
 * the invalidation. The [[invalidate]] causes invalidation when resolved; [[invalidateOn]]
 * causes invalidation upon dispatching a specific Muster event. See the [[dispatch]] to learn
 * more about dispatching Muster events.
 *
 * The predicate for the [[invalidateOn]] can be defined as:
 * - the type of the triggered event to respond to
 * - an array of triggered event types to respond to
 * - a function that takes [[EventData]] and returns a boolean
 *
 *
 * @example **Invalidating on event**
 * ```ts
 * import muster, { dispatch, fromPromise, invalidateOn, ref } from '@dws/muster';
 *
 * const externalNumbers = [1, 2, 3];
 *
 * const app = muster({
 *   numbers: invalidateOn(
 *     'invalidate-numbers',
 *     fromPromise(() => Promise.resolve(externalNumbers)),
 *   ),
 * });
 *
 * app.resolve(ref('numbers')).subscribe((numbers) => {
 *   console.log(numbers);
 * });
 *
 * console.log('Adding `4` to numbers`');
 * externalNumbers.push(4);
 *
 * console.log('Dispatching the `invalidate-numbers` event');
 * await app.resolve(dispatch('invalidate-numbers'));
 *
 * // Console output:
 * // [1, 2, 3]
 * // Adding `4` to numbers`
 * // Dispatching the `invalidate-numbers` event
 * // [1, 2, 3, 4]
 * ```
 * This example shows how to use the [[invalidateOn]] to invalidate a part of the graph when
 * a particular event is triggered.
 */
export declare function invalidateOn(predicate: AcceptedPredicateTypes, target: NodeLike): InvalidateOnNodeDefinition;
export declare function isInvalidateOnNodeDefinition(value: NodeDefinition): value is InvalidateOnNodeDefinition;