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import groupByLimit from './groupByLimit';
/**
* Returns a new object, where each value corresponds to an array of items, from
* `coll`, that returned the corresponding key. That is, the keys of the object
* correspond to the values passed to the `iteratee` callback.
*
* Note: Since this function applies the `iteratee` to each item in parallel,
* there is no guarantee that the `iteratee` functions will complete in order.
* However, the values for each key in the `result` will be in the same order as
* the original `coll`. For Objects, the values will roughly be in the order of
* the original Objects' keys (but this can vary across JavaScript engines).
*
* @name groupBy
* @static
* @memberOf module:Collections
* @method
* @category Collection
* @param {Array|Iterable|AsyncIterable|Object} coll - A collection to iterate over.
* @param {AsyncFunction} iteratee - An async function to apply to each item in
* `coll`.
* The iteratee should complete with a `key` to group the value under.
* Invoked with (value, callback).
* @param {Function} [callback] - A callback which is called when all `iteratee`
* functions have finished, or an error occurs. Result is an `Object` whoses
* properties are arrays of values which returned the corresponding key.
* @returns {Promise} a promise, if no callback is passed
* @example
*
* async.groupBy(['userId1', 'userId2', 'userId3'], function(userId, callback) {
* db.findById(userId, function(err, user) {
* if (err) return callback(err);
* return callback(null, user.age);
* });
* }, function(err, result) {
* // result is object containing the userIds grouped by age
* // e.g. { 30: ['userId1', 'userId3'], 42: ['userId2']};
* });
*/
export default function groupBy (coll, iteratee, callback) {
return groupByLimit(coll, Infinity, iteratee, callback)
}
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