81 lines
		
	
	
		
			2.5 KiB
		
	
	
	
		
			JavaScript
		
	
	
	
	
	
			
		
		
	
	
			81 lines
		
	
	
		
			2.5 KiB
		
	
	
	
		
			JavaScript
		
	
	
	
	
	
| 'use strict';
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| 
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| Object.defineProperty(exports, "__esModule", {
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|     value: true
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| });
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| exports.default = tryEach;
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| 
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| var _noop = require('lodash/noop');
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| 
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| var _noop2 = _interopRequireDefault(_noop);
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| 
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| var _eachSeries = require('./eachSeries');
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| 
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| var _eachSeries2 = _interopRequireDefault(_eachSeries);
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| 
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| var _wrapAsync = require('./internal/wrapAsync');
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| 
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| var _wrapAsync2 = _interopRequireDefault(_wrapAsync);
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| 
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| var _slice = require('./internal/slice');
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| 
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| var _slice2 = _interopRequireDefault(_slice);
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| 
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| function _interopRequireDefault(obj) { return obj && obj.__esModule ? obj : { default: obj }; }
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| 
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| /**
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|  * It runs each task in series but stops whenever any of the functions were
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|  * successful. If one of the tasks were successful, the `callback` will be
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|  * passed the result of the successful task. If all tasks fail, the callback
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|  * will be passed the error and result (if any) of the final attempt.
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|  *
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|  * @name tryEach
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|  * @static
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|  * @memberOf module:ControlFlow
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|  * @method
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|  * @category Control Flow
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|  * @param {Array|Iterable|Object} tasks - A collection containing functions to
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|  * run, each function is passed a `callback(err, result)` it must call on
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|  * completion with an error `err` (which can be `null`) and an optional `result`
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|  * value.
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|  * @param {Function} [callback] - An optional callback which is called when one
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|  * of the tasks has succeeded, or all have failed. It receives the `err` and
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|  * `result` arguments of the last attempt at completing the `task`. Invoked with
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|  * (err, results).
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|  * @example
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|  * async.tryEach([
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|  *     function getDataFromFirstWebsite(callback) {
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|  *         // Try getting the data from the first website
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|  *         callback(err, data);
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|  *     },
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|  *     function getDataFromSecondWebsite(callback) {
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|  *         // First website failed,
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|  *         // Try getting the data from the backup website
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|  *         callback(err, data);
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|  *     }
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|  * ],
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|  * // optional callback
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|  * function(err, results) {
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|  *     Now do something with the data.
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|  * });
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|  *
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|  */
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| function tryEach(tasks, callback) {
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|     var error = null;
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|     var result;
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|     callback = callback || _noop2.default;
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|     (0, _eachSeries2.default)(tasks, function (task, callback) {
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|         (0, _wrapAsync2.default)(task)(function (err, res /*, ...args*/) {
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|             if (arguments.length > 2) {
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|                 result = (0, _slice2.default)(arguments, 1);
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|             } else {
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|                 result = res;
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|             }
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|             error = err;
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|             callback(!err);
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|         });
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|     }, function () {
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|         callback(error, result);
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|     });
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| }
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| module.exports = exports['default']; |