import { StatelessGraphNode, StatelessNodeDefinition, StatelessNodeType } from '../../../types/graph';
/**
 * An instance of the [[firstItem]] node.
 * See the [[firstItem]] documentation to find out more.
 */
export interface FirstItemNode extends StatelessGraphNode<'firstItem', FirstItemNodeProperties> {
}
/**
 * A definition of the [[firstItem]] node.
 * See the [[firstItem]] documentation to find out more.
 */
export interface FirstItemNodeDefinition extends StatelessNodeDefinition<'firstItem', FirstItemNodeProperties> {
}
export interface FirstItemNodeProperties {
}
/**
 * The implementation of the [[firstItem]] node.
 * See the [[firstItem]] documentation to learn more.
 */
export declare const FirstItemNodeType: StatelessNodeType<'firstItem', FirstItemNodeProperties>;
/**
 * Creates a new instance of a [[firstItem]] node, which is a type of collection transform used
 * when taking the first item out of a collection.
 * This node serves as a fast implementation of the `take(1)`. It also comes with a shorthand
 * version to be used in the [ref](_utils_ref_.html#ref). See the **References to items in collections** example
 * from the [ref](_utils_ref_.html#ref) documentation.
 *
 *
 * @example **Take first item (using transform)**
 * ```js
 * import muster, { entries, firstItem, query, ref, withTransforms } from '@dws/muster';
 *
 * const app = muster({
 *   numbers: [1, 2, 3, 4, 5],
 * });
 *
 * const item = await app.resolve(query(ref('numbers'), withTransforms([
 *   firstItem(),
 * ], entries())));
 * // item === [1]
 * ```
 * This example shows how to use a [[firstItem]] transform to take the first item out of a
 * collection.
 */
export declare function firstItem(): FirstItemNodeDefinition;