internet-programming/lab3/node_modules/lowdb/examples/fp.md

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2023-11-02 02:38:40 +04:00
# lowdb/lib/fp
__:warning: Experimental__
`lowdb/lib/fp` lets you use [`lodash/fp`](https://github.com/lodash/lodash/wiki/FP-Guide), [`Ramda`](https://github.com/ramda/ramda) or simple JavaScript functions with lowdb.
It can help reducing the size of your `bundle.js`
## Usage
```js
import low from 'lowdb/lib/fp'
import { concat, find, sortBy, take, random } from 'lodash/fp'
const db = low()
// Get posts
const defaultValue = []
const posts = db('posts', defaultValue)
// replace posts with a new array resulting from concat
// and persist database
posts.write(
concat({ title: 'lowdb is awesome', views: random(0, 5) })
)
// Find post by id
const post = posts(
find({ id: 1 })
)
// Find top 5 fives posts
const popular = posts([
sortBy('views'),
take(5)
])
```
## API
`lowdb/lib/fp` shares the same API as `lowdb` except for the two following methods.
__db(path, [defaultValue])([funcs])__
Returns a new array or object without modifying the database state.
```js
db('posts')(filter({ published: true }))
```
__db(path, [defaultValue]).write([funcs])__
Add `.write` when you want the result to be written back to `path`
```js
db('posts').write(concat(newPost))
db('user.name').write(set('typicode'))
```