blob: eb8116806c298c81625c0f6474064bab57c385ed (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
|
# quick-lru [![Build Status](https://travis-ci.org/sindresorhus/quick-lru.svg?branch=master)](https://travis-ci.org/sindresorhus/quick-lru) [![Coverage Status](https://coveralls.io/repos/github/sindresorhus/quick-lru/badge.svg?branch=master)](https://coveralls.io/github/sindresorhus/quick-lru?branch=master)
> Simple ["Least Recently Used" (LRU) cache](https://en.m.wikipedia.org/wiki/Cache_replacement_policies#Least_Recently_Used_.28LRU.29)
Useful when you need to cache something and limit memory usage.
Inspired by the [`haslru` algorithm](https://github.com/dominictarr/hashlru#algorithm), but instead uses [`Map`](https://developer.mozilla.org/en/docs/Web/JavaScript/Reference/Global_Objects/Map) to support keys of any type, not just strings, and values can be `undefined`.
## Install
```
$ npm install quick-lru
```
## Usage
```js
const QuickLRU = require('quick-lru');
const lru = new QuickLRU({maxSize: 1000});
lru.set('π¦', 'π');
lru.has('π¦');
//=> true
lru.get('π¦');
//=> 'π'
```
## API
### new QuickLRU([options])
Returns a new instance.
### options
Type: `Object`
#### maxSize
*Required*<br>
Type: `Object`
Maximum number of items before evicting the least recently used items.
### Instance
The instance is [`iterable`](https://developer.mozilla.org/en/docs/Web/JavaScript/Reference/Iteration_protocols) so you can use it directly in a [`forβ¦of`](https://developer.mozilla.org/en/docs/Web/JavaScript/Reference/Statements/for...of) loop.
Both `key` and `value` can be of any type.
#### .set(key, value)
Set an item. Returns the instance.
#### .get(key)
Get an item.
#### .has(key)
Check if an item exists.
#### .peek(key)
Get an item without marking it as recently used.
#### .delete(key)
Delete an item.
#### .clear()
Delete all items.
#### .keys()
Iterable for all the keys.
#### .values()
Iterable for all the values.
#### .size
Get the item count.
## License
MIT Β© [Sindre Sorhus](https://sindresorhus.com)
|