map.js 2.28 KB
'use strict';

Object.defineProperty(exports, "__esModule", {
  value: true
});

var _map2 = require('./internal/map');

var _map3 = _interopRequireDefault(_map2);

var _eachOf = require('./eachOf');

var _eachOf2 = _interopRequireDefault(_eachOf);

var _awaitify = require('./internal/awaitify');

var _awaitify2 = _interopRequireDefault(_awaitify);

function _interopRequireDefault(obj) { return obj && obj.__esModule ? obj : { default: obj }; }

/**
 * Produces a new collection of values by mapping each value in `coll` through
 * the `iteratee` function. The `iteratee` is called with an item from `coll`
 * and a callback for when it has finished processing. Each of these callback
 * takes 2 arguments: an `error`, and the transformed item from `coll`. If
 * `iteratee` passes an error to its callback, the main `callback` (for the
 * `map` function) is immediately called with the error.
 *
 * Note, that 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 results array will be in the same order as the
 * original `coll`.
 *
 * If `map` is passed an Object, the results will be an Array.  The results
 * will roughly be in the order of the original Objects' keys (but this can
 * vary across JavaScript engines).
 *
 * @name map
 * @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 the transformed item.
 * Invoked with (item, callback).
 * @param {Function} [callback] - A callback which is called when all `iteratee`
 * functions have finished, or an error occurs. Results is an Array of the
 * transformed items from the `coll`. Invoked with (err, results).
 * @returns {Promise} a promise, if no callback is passed
 * @example
 *
 * async.map(['file1','file2','file3'], fs.stat, function(err, results) {
 *     // results is now an array of stats for each file
 * });
 */
function map(coll, iteratee, callback) {
  return (0, _map3.default)(_eachOf2.default, coll, iteratee, callback);
}
exports.default = (0, _awaitify2.default)(map, 3);
module.exports = exports['default'];