import { IndexedSelector } from "../types/IndexedSelector";
import { MapFactory } from "../types/MapFactory";
/**
 * Performs a full outer join by pairing elements from both iterables for every distinct key.
 *
 * @typeParam T - Element type produced by the left source iterable.
 * @typeParam TRight - Element type produced by the right source iterable.
 * @typeParam TKey - Key type generated by the key selector functions.
 * @typeParam TOut - Result type emitted by the `selector`.
 * @param src - Left source iterable evaluated for outer join matches.
 * @param rightSeq - Right source iterable evaluated for outer join matches.
 * @param leftKeySelector - Selector producing a key for each left element.
 * @param rightKeySelector - Selector producing a key for each right element.
 * @param selector - Projection receiving optional left and right elements plus the shared key.
 * @param mapFactory - Optional factory used to create the internal map for key lookups.
 * @returns A deferred iterable yielding the result of `selector` for each matched key combination.
 *
 * @example
 * ```ts
 * const result = [..._fullOuterJoin(
 *   [
 *     { id: 1, label: "L1" },
 *     { id: 2, label: "L2" }
 *   ],
 *   [
 *     { id: 2, label: "R2" },
 *     { id: 3, label: "R3" }
 *   ],
 *   (left) => left.id,
 *   (right) => right.id,
 *   (left, right, id) => ({
 *     id,
 *     left: left?.label,
 *     right: right?.label
 *   })
 * )];
 * console.log(result);
 * // [
 * //   { id: 1, left: "L1", right: undefined },
 * //   { id: 2, left: "L2", right: "R2" },
 * //   { id: 3, left: undefined, right: "R3" }
 * // ]
 * ```
 *
 * or using the curried version:
 * ```ts
 * const result = pipeInto(
 *   [
 *     { id: 1, name: "Alice" }
 *   ],
 *   fullOuterJoin(
 *     [
 *       { id: 1, city: "Paris" },
 *       { id: 2, city: "Rome" }
 *     ],
 *     (left) => left.id,
 *     (right) => right.id,
 *     (left, right, id) => ({
 *       id,
 *       name: left?.name ?? null,
 *       city: right?.city ?? null
 *     })
 *   )
 * );
 * console.log([...result]);
 * // [
 * //   { id: 1, name: "Alice", city: "Paris" },
 * //   { id: 2, name: null, city: "Rome" }
 * // ]
 * ```
 */
export declare function _fullOuterJoin<T, TRight, TKey, TOut>(src: Iterable<T>, rightSeq: Iterable<TRight>, leftKeySelector: IndexedSelector<T, TKey>, rightKeySelector: IndexedSelector<TRight, TKey>, selector: (o: T | undefined, v: TRight | undefined, k: TKey) => TOut, mapFactory?: MapFactory<TKey>): Iterable<TOut>;
/**
 * Curried version of {@link _fullOuterJoin}.
 */
export declare const fullOuterJoin: <T, TRight, TKey, TOut>(rightSeq: Iterable<TRight>, leftKeySelector: IndexedSelector<T, TKey>, rightKeySelector: IndexedSelector<TRight, TKey>, selector: (o: T | undefined, v: TRight | undefined, k: TKey) => TOut, mapFactory?: MapFactory<TKey> | undefined) => (src: Iterable<T>) => Iterable<TOut>;