summaryrefslogtreecommitdiff
path: root/doc
diff options
context:
space:
mode:
authorRam Goli <ramsgoli@gmail.com>2017-12-12 23:46:25 +0000
committerAnatoli Papirovski <apapirovski@mac.com>2017-12-17 13:19:03 -0500
commit3db136a74a34d610a0bea26f7da46ea2f33d96db (patch)
treeb68b2cb2b99b989e4bb020a21113794c42f0caca /doc
parentefffcc262c77a58ad3c75787497df46863d1b7a6 (diff)
downloadandroid-node-v8-3db136a74a34d610a0bea26f7da46ea2f33d96db.tar.gz
android-node-v8-3db136a74a34d610a0bea26f7da46ea2f33d96db.tar.bz2
android-node-v8-3db136a74a34d610a0bea26f7da46ea2f33d96db.zip
doc: change "Node.js style cb" to "error-first cb"
Change the awkward "Node.js style callback" phrasing to the more informative "error-first callback." PR-URL: https://github.com/nodejs/node/pull/17638 Reviewed-By: James M Snell <jasnell@gmail.com> Reviewed-By: Vse Mozhet Byt <vsemozhetbyt@gmail.com> Reviewed-By: Jon Moss <me@jonathanmoss.me> Reviewed-By: Rich Trott <rtrott@gmail.com> Reviewed-By: Gireesh Punathil <gpunathi@in.ibm.com> Reviewed-By: Ruben Bridgewater <ruben@bridgewater.de> Reviewed-By: Colin Ihrig <cjihrig@gmail.com> Reviewed-By: Luigi Pinca <luigipinca@gmail.com> Reviewed-By: Jeremiah Senkpiel <fishrock123@rocketmail.com>
Diffstat (limited to 'doc')
-rw-r--r--doc/api/errors.md21
-rw-r--r--doc/api/util.md17
2 files changed, 20 insertions, 18 deletions
diff --git a/doc/api/errors.md b/doc/api/errors.md
index fab75e9bc4..776639d2e4 100644
--- a/doc/api/errors.md
+++ b/doc/api/errors.md
@@ -128,21 +128,22 @@ they are thrown *after* the calling code has already exited.
Developers must refer to the documentation for each method to determine
exactly how errors raised by those methods are propagated.
-### Node.js style callbacks
+### Error-first callbacks
<!--type=misc-->
Most asynchronous methods exposed by the Node.js core API follow an idiomatic
-pattern referred to as a "Node.js style callback". With this pattern, a
-callback function is passed to the method as an argument. When the operation
-either completes or an error is raised, the callback function is called with
-the Error object (if any) passed as the first argument. If no error was raised,
-the first argument will be passed as `null`.
+pattern referred to as an _error-first callback_ (sometimes referred to as
+a _Node.js style callback_). With this pattern, a callback function is passed
+to the method as an argument. When the operation either completes or an error
+is raised, the callback function is called with
+the Error object (if any) passed as the first argument. If no error was
+raised, the first argument will be passed as `null`.
```js
const fs = require('fs');
-function nodeStyleCallback(err, data) {
+function errorFirstCallback(err, data) {
if (err) {
console.error('There was an error', err);
return;
@@ -150,13 +151,13 @@ function nodeStyleCallback(err, data) {
console.log(data);
}
-fs.readFile('/some/file/that/does-not-exist', nodeStyleCallback);
-fs.readFile('/some/file/that/does-exist', nodeStyleCallback);
+fs.readFile('/some/file/that/does-not-exist', errorFirstCallback);
+fs.readFile('/some/file/that/does-exist', errorFirstCallback);
```
The JavaScript `try / catch` mechanism **cannot** be used to intercept errors
generated by asynchronous APIs. A common mistake for beginners is to try to
-use `throw` inside a Node.js style callback:
+use `throw` inside an error-first callback:
```js
// THIS WILL NOT WORK:
diff --git a/doc/api/util.md b/doc/api/util.md
index 1e72954126..c653802d3d 100644
--- a/doc/api/util.md
+++ b/doc/api/util.md
@@ -21,9 +21,10 @@ added: v8.2.0
* Returns: {Function} a callback style function
Takes an `async` function (or a function that returns a Promise) and returns a
-function following the Node.js error first callback style. In the callback, the
-first argument will be the rejection reason (or `null` if the Promise resolved),
-and the second argument will be the resolved value.
+function following the error-first callback style, i.e. taking
+a `(err, value) => ...` callback as the last argument. In the callback, the
+first argument will be the rejection reason (or `null` if the Promise
+resolved), and the second argument will be the resolved value.
For example:
@@ -530,8 +531,8 @@ added: v8.0.0
* `original` {Function}
* Returns: {Function}
-Takes a function following the common Node.js callback style, i.e. taking a
-`(err, value) => ...` callback as the last argument, and returns a version
+Takes a function following the common error-first callback style, i.e. taking
+a `(err, value) => ...` callback as the last argument, and returns a version
that returns promises.
For example:
@@ -567,9 +568,9 @@ will return its value, see [Custom promisified functions][].
`promisify()` assumes that `original` is a function taking a callback as its
final argument in all cases. If `original` is not a function, `promisify()`
-will throw an error. If `original` is a function but its last argument is not a
-Node.js style callback, it will still be passed a Node.js style callback
-as its last argument.
+will throw an error. If `original` is a function but its last argument is not
+an error-first callback, it will still be passed an error-first
+callback as its last argument.
### Custom promisified functions