142 lines
4.5 KiB
JavaScript
142 lines
4.5 KiB
JavaScript
'use strict';
|
|
|
|
Object.defineProperty(exports, "__esModule", {
|
|
value: true
|
|
});
|
|
|
|
var _map2 = require('./internal/map.js');
|
|
|
|
var _map3 = _interopRequireDefault(_map2);
|
|
|
|
var _eachOf = require('./eachOf.js');
|
|
|
|
var _eachOf2 = _interopRequireDefault(_eachOf);
|
|
|
|
var _awaitify = require('./internal/awaitify.js');
|
|
|
|
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 callbacks
|
|
* 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
|
|
*
|
|
* // file1.txt is a file that is 1000 bytes in size
|
|
* // file2.txt is a file that is 2000 bytes in size
|
|
* // file3.txt is a file that is 3000 bytes in size
|
|
* // file4.txt does not exist
|
|
*
|
|
* const fileList = ['file1.txt','file2.txt','file3.txt'];
|
|
* const withMissingFileList = ['file1.txt','file2.txt','file4.txt'];
|
|
*
|
|
* // asynchronous function that returns the file size in bytes
|
|
* function getFileSizeInBytes(file, callback) {
|
|
* fs.stat(file, function(err, stat) {
|
|
* if (err) {
|
|
* return callback(err);
|
|
* }
|
|
* callback(null, stat.size);
|
|
* });
|
|
* }
|
|
*
|
|
* // Using callbacks
|
|
* async.map(fileList, getFileSizeInBytes, function(err, results) {
|
|
* if (err) {
|
|
* console.log(err);
|
|
* } else {
|
|
* console.log(results);
|
|
* // results is now an array of the file size in bytes for each file, e.g.
|
|
* // [ 1000, 2000, 3000]
|
|
* }
|
|
* });
|
|
*
|
|
* // Error Handling
|
|
* async.map(withMissingFileList, getFileSizeInBytes, function(err, results) {
|
|
* if (err) {
|
|
* console.log(err);
|
|
* // [ Error: ENOENT: no such file or directory ]
|
|
* } else {
|
|
* console.log(results);
|
|
* }
|
|
* });
|
|
*
|
|
* // Using Promises
|
|
* async.map(fileList, getFileSizeInBytes)
|
|
* .then( results => {
|
|
* console.log(results);
|
|
* // results is now an array of the file size in bytes for each file, e.g.
|
|
* // [ 1000, 2000, 3000]
|
|
* }).catch( err => {
|
|
* console.log(err);
|
|
* });
|
|
*
|
|
* // Error Handling
|
|
* async.map(withMissingFileList, getFileSizeInBytes)
|
|
* .then( results => {
|
|
* console.log(results);
|
|
* }).catch( err => {
|
|
* console.log(err);
|
|
* // [ Error: ENOENT: no such file or directory ]
|
|
* });
|
|
*
|
|
* // Using async/await
|
|
* async () => {
|
|
* try {
|
|
* let results = await async.map(fileList, getFileSizeInBytes);
|
|
* console.log(results);
|
|
* // results is now an array of the file size in bytes for each file, e.g.
|
|
* // [ 1000, 2000, 3000]
|
|
* }
|
|
* catch (err) {
|
|
* console.log(err);
|
|
* }
|
|
* }
|
|
*
|
|
* // Error Handling
|
|
* async () => {
|
|
* try {
|
|
* let results = await async.map(withMissingFileList, getFileSizeInBytes);
|
|
* console.log(results);
|
|
* }
|
|
* catch (err) {
|
|
* console.log(err);
|
|
* // [ Error: ENOENT: no such file or directory ]
|
|
* }
|
|
* }
|
|
*
|
|
*/
|
|
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']; |