/**
 * Executes async functions in parallel with a concurrency limit
 * @param {number} limit - Maximum number of concurrent executions
 * @param {T[]} items - The items to process
 * @param {(item: T, index: number) => Promise<U>} function_ - The async function to apply to each item
 * @returns {Promise<U[]>} Results in the same order as the input items
 * @example
 * const results = await parallel(2, [1, 2, 3], async (n) => n * 2);
 */
export declare const parallel: <T, U>(limit: number, items: T[], function_: (item: T, index: number) => Promise<U>) => Promise<U[]>;