gotosocial/vendor/github.com/hashicorp/golang-lru/v2/README.md

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golang-lru
==========
This provides the `lru` package which implements a fixed-size
thread safe LRU cache. It is based on the cache in Groupcache.
Documentation
=============
Full docs are available on [Go Packages](https://pkg.go.dev/github.com/hashicorp/golang-lru/v2)
LRU cache example
=================
```go
package main
import (
"fmt"
"github.com/hashicorp/golang-lru/v2"
)
func main() {
l, _ := lru.New[int, any](128)
for i := 0; i < 256; i++ {
l.Add(i, nil)
}
if l.Len() != 128 {
panic(fmt.Sprintf("bad len: %v", l.Len()))
}
}
```
Expirable LRU cache example
===========================
```go
package main
import (
"fmt"
"time"
"github.com/hashicorp/golang-lru/v2/expirable"
)
func main() {
// make cache with 10ms TTL and 5 max keys
cache := expirable.NewLRU[string, string](5, nil, time.Millisecond*10)
// set value under key1.
cache.Add("key1", "val1")
// get value under key1
r, ok := cache.Get("key1")
// check for OK value
if ok {
fmt.Printf("value before expiration is found: %v, value: %q\n", ok, r)
}
// wait for cache to expire
time.Sleep(time.Millisecond * 12)
// get value under key1 after key expiration
r, ok = cache.Get("key1")
fmt.Printf("value after expiration is found: %v, value: %q\n", ok, r)
// set value under key2, would evict old entry because it is already expired.
cache.Add("key2", "val2")
fmt.Printf("Cache len: %d\n", cache.Len())
// Output:
// value before expiration is found: true, value: "val1"
// value after expiration is found: false, value: ""
// Cache len: 1
}
```