import { ArrayIterator } from '../_internal/ArrayIterator.js';
import { ListIterator } from '../_internal/ListIterator.js';
import { ObjectIterator } from '../_internal/ObjectIterator.js';
import { StringIterator } from '../_internal/StringIterator.js';

/**
 * Iterates over elements of array and invokes iteratee for each element.
 *
 * @template T
 * @param {T[]} collection - The array to iterate over.
 * @param {ArrayIterator<T, any>} [iteratee] - The function invoked per iteration.
 * @returns {T[]} Returns array.
 *
 * @example
 * forEach([1, 2], value => console.log(value));
 * // => Logs `1` then `2`.
 */
declare function forEach<T>(collection: T[], iteratee?: ArrayIterator<T, any>): T[];
/**
 * Iterates over characters of string and invokes iteratee for each character.
 *
 * @param {string} collection - The string to iterate over.
 * @param {StringIterator<any>} [iteratee] - The function invoked per iteration.
 * @returns {string} Returns string.
 *
 * @example
 * forEach('abc', char => console.log(char));
 * // => Logs 'a', 'b', then 'c'.
 */
declare function forEach(collection: string, iteratee?: StringIterator<any>): string;
/**
 * Iterates over elements of collection and invokes iteratee for each element.
 *
 * @template T
 * @param {ArrayLike<T>} collection - The collection to iterate over.
 * @param {ListIterator<T, any>} [iteratee] - The function invoked per iteration.
 * @returns {ArrayLike<T>} Returns collection.
 *
 * @example
 * forEach({ 0: 'a', 1: 'b', length: 2 }, value => console.log(value));
 * // => Logs 'a' then 'b'.
 */
declare function forEach<T>(collection: ArrayLike<T>, iteratee?: ListIterator<T, any>): ArrayLike<T>;
/**
 * Iterates over own enumerable string keyed properties of an object and invokes iteratee for each property.
 *
 * @template T
 * @param {T} collection - The object to iterate over.
 * @param {ObjectIterator<T, any>} [iteratee] - The function invoked per iteration.
 * @returns {T} Returns object.
 *
 * @example
 * forEach({ a: 1, b: 2 }, (value, key) => console.log(key));
 * // => Logs 'a' then 'b'.
 */
declare function forEach<T extends object>(collection: T, iteratee?: ObjectIterator<T, any>): T;
/**
 * Iterates over elements of array and invokes iteratee for each element.
 *
 * @template T, U
 * @param {U & (T[] | null | undefined)} collection - The array to iterate over.
 * @param {ArrayIterator<T, any>} [iteratee] - The function invoked per iteration.
 * @returns {U} Returns the array.
 *
 * @example
 * forEach([1, 2], value => console.log(value));
 * // => Logs `1` then `2`.
 */
declare function forEach<T, U extends T[] | null | undefined>(collection: U & (T[] | null | undefined), iteratee?: ArrayIterator<T, any>): U;
/**
 * Iterates over characters of string and invokes iteratee for each character.
 *
 * @template T
 * @param {T} collection - The string to iterate over.
 * @param {StringIterator<any>} [iteratee] - The function invoked per iteration.
 * @returns {T} Returns the string.
 *
 * @example
 * forEach('abc', char => console.log(char));
 * // => Logs 'a', 'b', then 'c'.
 */
declare function forEach<T extends string | null | undefined>(collection: T, iteratee?: StringIterator<any>): T;
/**
 * Iterates over elements of collection and invokes iteratee for each element.
 *
 * @template T, L
 * @param {L & (ArrayLike<T> | null | undefined)} collection - The collection to iterate over.
 * @param {ListIterator<T, any>} [iteratee] - The function invoked per iteration.
 * @returns {L} Returns the collection.
 *
 * @example
 * forEach({ 0: 'a', 1: 'b', length: 2 }, value => console.log(value));
 * // => Logs 'a' then 'b'.
 */
declare function forEach<T, L extends ArrayLike<T> | null | undefined>(collection: L & (ArrayLike<T> | null | undefined), iteratee?: ListIterator<T, any>): L;
/**
 * Iterates over own enumerable string keyed properties of an object and invokes iteratee for each property.
 *
 * @template T
 * @param {T | null | undefined} collection - The object to iterate over.
 * @param {ObjectIterator<T, any>} [iteratee] - The function invoked per iteration.
 * @returns {T | null | undefined} Returns the object.
 *
 * @example
 * forEach({ a: 1, b: 2 }, (value, key) => console.log(key));
 * // => Logs 'a' then 'b'.
 */
declare function forEach<T extends object>(collection: T | null | undefined, iteratee?: ObjectIterator<T, any>): T | null | undefined;

export { forEach };