'use strict';

import eachOfLimit from './internal/eachOfLimit';
import withoutIndex from './internal/withoutIndex';

/**
 * The same as `each` but runs a maximum of `limit` async operations at a time.
 *
 * @name eachLimit
 * @static
 * @memberOf async
 * @see `async.each`
 * @alias forEachLimit
 * @category Collection
 * @param {Array|Object} coll - A colleciton to iterate over.
 * @param {number} limit - The maximum number of async operations at a time.
 * @param {Function} iteratee - A function to apply to each item in `coll`. The
 * iteratee is passed a `callback(err)` which must be called once it has
 * completed. If no error has occurred, the `callback` should be run without
 * arguments or with an explicit `null` argument. The array index is not passed
 * to the iteratee. Invoked with (item, callback). If you need the index, use
 * `eachOfLimit`.
 * @param {Function} [callback] - A callback which is called when all
 * `iteratee` functions have finished, or an error occurs. Invoked with (err).
 */
export default function eachLimit(arr, limit, iteratee, cb) {
    return eachOfLimit(limit)(arr, withoutIndex(iteratee), cb);
}