1golang-lru
2==========
3
4This provides the `lru` package which implements a fixed-size
5thread safe LRU cache. It is based on the cache in Groupcache.
6
7Documentation
8=============
9
10Full docs are available on [Go Packages](https://pkg.go.dev/github.com/hashicorp/golang-lru/v2)
11
12LRU cache example
13=================
14
15```go
16package main
17
18import (
19 "fmt"
20 "github.com/hashicorp/golang-lru/v2"
21)
22
23func main() {
24 l, _ := lru.New[int, any](128)
25 for i := 0; i < 256; i++ {
26 l.Add(i, nil)
27 }
28 if l.Len() != 128 {
29 panic(fmt.Sprintf("bad len: %v", l.Len()))
30 }
31}
32```
33
34Expirable LRU cache example
35===========================
36
37```go
38package main
39
40import (
41 "fmt"
42 "time"
43
44 "github.com/hashicorp/golang-lru/v2/expirable"
45)
46
47func main() {
48 // make cache with 10ms TTL and 5 max keys
49 cache := expirable.NewLRU[string, string](5, nil, time.Millisecond*10)
50
51
52 // set value under key1.
53 cache.Add("key1", "val1")
54
55 // get value under key1
56 r, ok := cache.Get("key1")
57
58 // check for OK value
59 if ok {
60 fmt.Printf("value before expiration is found: %v, value: %q\n", ok, r)
61 }
62
63 // wait for cache to expire
64 time.Sleep(time.Millisecond * 12)
65
66 // get value under key1 after key expiration
67 r, ok = cache.Get("key1")
68 fmt.Printf("value after expiration is found: %v, value: %q\n", ok, r)
69
70 // set value under key2, would evict old entry because it is already expired.
71 cache.Add("key2", "val2")
72
73 fmt.Printf("Cache len: %d\n", cache.Len())
74 // Output:
75 // value before expiration is found: true, value: "val1"
76 // value after expiration is found: false, value: ""
77 // Cache len: 1
78}
79```
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