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-rw-r--r--docs/v3/transform.js.html122
1 files changed, 107 insertions, 15 deletions
diff --git a/docs/v3/transform.js.html b/docs/v3/transform.js.html
index 2bce88e..cb5324a 100644
--- a/docs/v3/transform.js.html
+++ b/docs/v3/transform.js.html
@@ -102,26 +102,118 @@ import { promiseCallback, PROMISE_SYMBOL } from './internal/promiseCallback
* @returns {Promise} a promise, if no callback provided
* @example
*
- * async.transform([1,2,3], function(acc, item, index, callback) {
- * // pointless async:
- * process.nextTick(function() {
- * acc[index] = item * 2
- * callback(null)
+ * // 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
+ *
+ * // helper function that returns human-readable size format from bytes
+ * function formatBytes(bytes, decimals = 2) {
+ * // implementation not included for brevity
+ * return humanReadbleFilesize;
+ * }
+ *
+ * const fileList = ['file1.txt','file2.txt','file3.txt'];
+ *
+ * // asynchronous function that returns the file size, transformed to human-readable format
+ * // e.g. 1024 bytes = 1KB, 1234 bytes = 1.21 KB, 1048576 bytes = 1MB, etc.
+ * function transformFileSize(acc, value, key, callback) {
+ * fs.stat(value, function(err, stat) {
+ * if (err) {
+ * return callback(err);
+ * }
+ * acc[key] = formatBytes(stat.size);
+ * callback(null);
* });
- * }, function(err, result) {
- * // result is now equal to [2, 4, 6]
+ * }
+ *
+ * // Using callbacks
+ * async.transform(fileList, transformFileSize, function(err, result) {
+ * if(err) {
+ * console.log(err);
+ * } else {
+ * console.log(result);
+ * // [ '1000 Bytes', '1.95 KB', '2.93 KB' ]
+ * }
* });
*
+ * // Using Promises
+ * async.transform(fileList, transformFileSize)
+ * .then(result => {
+ * console.log(result);
+ * // [ '1000 Bytes', '1.95 KB', '2.93 KB' ]
+ * }).catch(err => {
+ * console.log(err);
+ * });
+ *
+ * // Using async/await
+ * (async () => {
+ * try {
+ * let result = await async.transform(fileList, transformFileSize);
+ * console.log(result);
+ * // [ '1000 Bytes', '1.95 KB', '2.93 KB' ]
+ * }
+ * catch (err) {
+ * console.log(err);
+ * }
+ * })();
+ *
* @example
*
- * async.transform({a: 1, b: 2, c: 3}, function (obj, val, key, callback) {
- * setImmediate(function () {
- * obj[key] = val * 2;
- * callback();
- * })
- * }, function (err, result) {
- * // result is equal to {a: 2, b: 4, c: 6}
- * })
+ * // 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
+ *
+ * // helper function that returns human-readable size format from bytes
+ * function formatBytes(bytes, decimals = 2) {
+ * // implementation not included for brevity
+ * return humanReadbleFilesize;
+ * }
+ *
+ * const fileMap = { f1: 'file1.txt', f2: 'file2.txt', f3: 'file3.txt' };
+ *
+ * // asynchronous function that returns the file size, transformed to human-readable format
+ * // e.g. 1024 bytes = 1KB, 1234 bytes = 1.21 KB, 1048576 bytes = 1MB, etc.
+ * function transformFileSize(acc, value, key, callback) {
+ * fs.stat(value, function(err, stat) {
+ * if (err) {
+ * return callback(err);
+ * }
+ * acc[key] = formatBytes(stat.size);
+ * callback(null);
+ * });
+ * }
+ *
+ * // Using callbacks
+ * async.transform(fileMap, transformFileSize, function(err, result) {
+ * if(err) {
+ * console.log(err);
+ * } else {
+ * console.log(result);
+ * // { f1: '1000 Bytes', f2: '1.95 KB', f3: '2.93 KB' }
+ * }
+ * });
+ *
+ * // Using Promises
+ * async.transform(fileMap, transformFileSize)
+ * .then(result => {
+ * console.log(result);
+ * // { f1: '1000 Bytes', f2: '1.95 KB', f3: '2.93 KB' }
+ * }).catch(err => {
+ * console.log(err);
+ * });
+ *
+ * // Using async/await
+ * async () => {
+ * try {
+ * let result = await async.transform(fileMap, transformFileSize);
+ * console.log(result);
+ * // { f1: '1000 Bytes', f2: '1.95 KB', f3: '2.93 KB' }
+ * }
+ * catch (err) {
+ * console.log(err);
+ * }
+ * }
+ *
*/
export default function transform (coll, accumulator, iteratee, callback) {
if (arguments.length <= 3 && typeof accumulator === 'function') {