; | |
Object.defineProperty(exports, "__esModule", { | |
value: true | |
}); | |
exports.default = groupBy; | |
var _groupByLimit = require('./groupByLimit.js'); | |
var _groupByLimit2 = _interopRequireDefault(_groupByLimit); | |
function _interopRequireDefault(obj) { return obj && obj.__esModule ? obj : { default: obj }; } | |
/** | |
* Returns a new object, where each value corresponds to an array of items, from | |
* `coll`, that returned the corresponding key. That is, the keys of the object | |
* correspond to the values passed to the `iteratee` callback. | |
* | |
* Note: 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 values for each key in the `result` will be in the same order as | |
* the original `coll`. For Objects, the values will roughly be in the order of | |
* the original Objects' keys (but this can vary across JavaScript engines). | |
* | |
* @name groupBy | |
* @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 a `key` to group the value under. | |
* Invoked with (value, callback). | |
* @param {Function} [callback] - A callback which is called when all `iteratee` | |
* functions have finished, or an error occurs. Result is an `Object` whoses | |
* properties are arrays of values which returned the corresponding key. | |
* @returns {Promise} a promise, if no callback is passed | |
* @example | |
* | |
* // 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 | |
* // dir4 does not exist | |
* | |
* const files = ['dir1/file1.txt','dir2','dir4'] | |
* | |
* // asynchronous function that detects file type as none, file, or directory | |
* function detectFile(file, callback) { | |
* fs.stat(file, function(err, stat) { | |
* if (err) { | |
* return callback(null, 'none'); | |
* } | |
* callback(null, stat.isDirectory() ? 'directory' : 'file'); | |
* }); | |
* } | |
* | |
* //Using callbacks | |
* async.groupBy(files, detectFile, function(err, result) { | |
* if(err) { | |
* console.log(err); | |
* } else { | |
* console.log(result); | |
* // { | |
* // file: [ 'dir1/file1.txt' ], | |
* // none: [ 'dir4' ], | |
* // directory: [ 'dir2'] | |
* // } | |
* // result is object containing the files grouped by type | |
* } | |
* }); | |
* | |
* // Using Promises | |
* async.groupBy(files, detectFile) | |
* .then( result => { | |
* console.log(result); | |
* // { | |
* // file: [ 'dir1/file1.txt' ], | |
* // none: [ 'dir4' ], | |
* // directory: [ 'dir2'] | |
* // } | |
* // result is object containing the files grouped by type | |
* }).catch( err => { | |
* console.log(err); | |
* }); | |
* | |
* // Using async/await | |
* async () => { | |
* try { | |
* let result = await async.groupBy(files, detectFile); | |
* console.log(result); | |
* // { | |
* // file: [ 'dir1/file1.txt' ], | |
* // none: [ 'dir4' ], | |
* // directory: [ 'dir2'] | |
* // } | |
* // result is object containing the files grouped by type | |
* } | |
* catch (err) { | |
* console.log(err); | |
* } | |
* } | |
* | |
*/ | |
function groupBy(coll, iteratee, callback) { | |
return (0, _groupByLimit2.default)(coll, Infinity, iteratee, callback); | |
} | |
module.exports = exports.default; |