mirror of
https://github.com/actions/setup-python
synced 2024-11-30 21:22:28 +08:00
155 lines
4.8 KiB
Markdown
155 lines
4.8 KiB
Markdown
# map-visit [](https://www.npmjs.com/package/map-visit) [](https://npmjs.org/package/map-visit) [](https://npmjs.org/package/map-visit) [](https://travis-ci.org/jonschlinkert/map-visit)
|
|
|
|
> Map `visit` over an array of objects.
|
|
|
|
## Install
|
|
|
|
Install with [npm](https://www.npmjs.com/):
|
|
|
|
```sh
|
|
$ npm install --save map-visit
|
|
```
|
|
|
|
## Usage
|
|
|
|
```js
|
|
var mapVisit = require('map-visit');
|
|
```
|
|
|
|
## What does this do?
|
|
|
|
**Assign/Merge/Extend vs. Visit**
|
|
|
|
Let's say you want to add a `set` method to your application that will:
|
|
|
|
* set key-value pairs on a `data` object
|
|
* extend objects onto the `data` object
|
|
* extend arrays of objects onto the data object
|
|
|
|
**Example using `extend`**
|
|
|
|
Here is one way to accomplish this using Lo-Dash's `extend` (comparable to `Object.assign`):
|
|
|
|
```js
|
|
var _ = require('lodash');
|
|
|
|
var obj = {
|
|
data: {},
|
|
set: function (key, value) {
|
|
if (Array.isArray(key)) {
|
|
_.extend.apply(_, [obj.data].concat(key));
|
|
} else if (typeof key === 'object') {
|
|
_.extend(obj.data, key);
|
|
} else {
|
|
obj.data[key] = value;
|
|
}
|
|
}
|
|
};
|
|
|
|
obj.set('a', 'a');
|
|
obj.set([{b: 'b'}, {c: 'c'}]);
|
|
obj.set({d: {e: 'f'}});
|
|
|
|
console.log(obj.data);
|
|
//=> {a: 'a', b: 'b', c: 'c', d: { e: 'f' }}
|
|
```
|
|
|
|
The above approach works fine for most use cases. However, **if you also want to emit an event** each time a property is added to the `data` object, or you want more control over what happens as the object is extended, a better approach would be to use `visit`.
|
|
|
|
**Example using `visit`**
|
|
|
|
In this approach:
|
|
|
|
* when an array is passed to `set`, the `mapVisit` library calls the `set` method on each object in the array.
|
|
* when an object is passed, `visit` calls `set` on each property in the object.
|
|
|
|
As a result, the `data` event will be emitted every time a property is added to `data` (events are just an example, you can use this approach to perform any necessary logic every time the method is called).
|
|
|
|
```js
|
|
var mapVisit = require('map-visit');
|
|
var visit = require('object-visit');
|
|
|
|
var obj = {
|
|
data: {},
|
|
set: function (key, value) {
|
|
if (Array.isArray(key)) {
|
|
mapVisit(obj, 'set', key);
|
|
} else if (typeof key === 'object') {
|
|
visit(obj, 'set', key);
|
|
} else {
|
|
// simulate an event-emitter
|
|
console.log('emit', key, value);
|
|
obj.data[key] = value;
|
|
}
|
|
}
|
|
};
|
|
|
|
obj.set('a', 'a');
|
|
obj.set([{b: 'b'}, {c: 'c'}]);
|
|
obj.set({d: {e: 'f'}});
|
|
obj.set({g: 'h', i: 'j', k: 'l'});
|
|
|
|
console.log(obj.data);
|
|
//=> {a: 'a', b: 'b', c: 'c', d: { e: 'f' }, g: 'h', i: 'j', k: 'l'}
|
|
|
|
// events would look something like:
|
|
// emit a a
|
|
// emit b b
|
|
// emit c c
|
|
// emit d { e: 'f' }
|
|
// emit g h
|
|
// emit i j
|
|
// emit k l
|
|
```
|
|
|
|
## About
|
|
|
|
### Related projects
|
|
|
|
* [collection-visit](https://www.npmjs.com/package/collection-visit): Visit a method over the items in an object, or map visit over the objects… [more](https://github.com/jonschlinkert/collection-visit) | [homepage](https://github.com/jonschlinkert/collection-visit "Visit a method over the items in an object, or map visit over the objects in an array.")
|
|
* [object-visit](https://www.npmjs.com/package/object-visit): Call a specified method on each value in the given object. | [homepage](https://github.com/jonschlinkert/object-visit "Call a specified method on each value in the given object.")
|
|
|
|
### Contributing
|
|
|
|
Pull requests and stars are always welcome. For bugs and feature requests, [please create an issue](../../issues/new).
|
|
|
|
### Contributors
|
|
|
|
| **Commits** | **Contributor** |
|
|
| --- | --- |
|
|
| 15 | [jonschlinkert](https://github.com/jonschlinkert) |
|
|
| 7 | [doowb](https://github.com/doowb) |
|
|
|
|
### Building docs
|
|
|
|
_(This project's readme.md is generated by [verb](https://github.com/verbose/verb-generate-readme), please don't edit the readme directly. Any changes to the readme must be made in the [.verb.md](.verb.md) readme template.)_
|
|
|
|
To generate the readme, run the following command:
|
|
|
|
```sh
|
|
$ npm install -g verbose/verb#dev verb-generate-readme && verb
|
|
```
|
|
|
|
### Running tests
|
|
|
|
Running and reviewing unit tests is a great way to get familiarized with a library and its API. You can install dependencies and run tests with the following command:
|
|
|
|
```sh
|
|
$ npm install && npm test
|
|
```
|
|
|
|
### Author
|
|
|
|
**Jon Schlinkert**
|
|
|
|
* [github/jonschlinkert](https://github.com/jonschlinkert)
|
|
* [twitter/jonschlinkert](https://twitter.com/jonschlinkert)
|
|
|
|
### License
|
|
|
|
Copyright © 2017, [Jon Schlinkert](https://github.com/jonschlinkert).
|
|
Released under the [MIT License](LICENSE).
|
|
|
|
***
|
|
|
|
_This file was generated by [verb-generate-readme](https://github.com/verbose/verb-generate-readme), v0.5.0, on April 09, 2017._ |