diff options
Diffstat (limited to 'lib/reject.js')
-rw-r--r-- | lib/reject.js | 48 |
1 files changed, 41 insertions, 7 deletions
diff --git a/lib/reject.js b/lib/reject.js index c1de825..127430e 100644 --- a/lib/reject.js +++ b/lib/reject.js @@ -21,14 +21,48 @@ import awaitify from './internal/awaitify' * @returns {Promise} a promise, if no callback is passed * @example * - * async.reject(['file1','file2','file3'], function(filePath, callback) { - * fs.access(filePath, function(err) { - * callback(null, !err) - * }); - * }, function(err, results) { - * // results now equals an array of missing files - * createFiles(results); + * // dir1 is a directory that contains file1.txt, file2.txt + * // dir2 is a directory that contains file3.txt, file4.txt + * // dir3 is a directory that contains file5.txt + * + * const fileList = ['dir1/file1.txt','dir2/file3.txt','dir3/file6.txt']; + * + * // asynchronous function that checks if a file exists + * function fileExists(file, callback) { + * fs.access(file, fs.constants.F_OK, (err) => { + * callback(null, !err); + * }); + * } + * + * // Using callbacks + * async.reject(fileList, fileExists, function(err, results) { + * // [ 'dir3/file6.txt' ] + * // results now equals an array of the non-existing files * }); + * + * // Using Promises + * async.reject(fileList, fileExists) + * .then( results => { + * console.log(results); + * // [ 'dir3/file6.txt' ] + * // results now equals an array of the non-existing files + * }).catch( err => { + * console.log(err); + * }); + * + * // Using async/await + * async () => { + * try { + * let results = await async.reject(fileList, fileExists); + * console.log(results); + * // [ 'dir3/file6.txt' ] + * // results now equals an array of the non-existing files + * } + * catch (err) { + * console.log(err); + * } + * } + * */ function reject (coll, iteratee, callback) { return _reject(eachOf, coll, iteratee, callback) |