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+import noop from 'lodash/noop';
+import eachSeries from './eachSeries';
+import rest from './internal/rest';
+
+/**
+ * It runs each task in series but stops whenever any of the functions were
+ * successful. If one of the tasks were successful, the `callback` will be
+ * passed the result of the successful task. If all tasks fail, the callback
+ * will be passed the error and result (if any) of the final attempt.
+ *
+ * @name tryEach
+ * @static
+ * @memberOf module:ControlFlow
+ * @method
+ * @category Control Flow
+ * @param {Array|Iterable|Object} tasks - A collection containing functions to
+ * run, each function is passed a `callback(err, result)` it must call on
+ * completion with an error `err` (which can be `null`) and an optional `result`
+ * value.
+ * @param {Function} [callback] - An optional callback which is called when one
+ * of the tasks has succeeded, or all have failed. It receives the `err` and
+ * `result` arguments of the last attempt at completing the `task`. Invoked with
+ * (err, results).
+ * @example
+ * async.try([
+ * function getDataFromFirstWebsite(callback) {
+ * // Try getting the data from the first website
+ * callback(err, data);
+ * },
+ * function getDataFromSecondWebsite(callback) {
+ * // First website failed,
+ * // Try getting the data from the backup website
+ * callback(err, data);
+ * }
+ * ],
+ * // optional callback
+ * function(err, results) {
+ * Now do something with the data.
+ * });
+ *
+ */
+export default function tryEach(tasks, callback) {
+ var error = null;
+ var result;
+ callback = callback || noop;
+ eachSeries(tasks, function(task, callback) {
+ task(rest(function (err, args) {
+ if (args.length <= 1) {
+ args = args[0];
+ }
+ error = err;
+ result = args;
+ callback(!err);
+ }));
+ }, function () {
+ callback(error, result);
+ });
+}