lru

README

LRU utilities

This package is a fork of https://github.com/hashicorp/golang-lru

Documentation

Index

• Constants
• type Cache
  • func New[K comparable, V any](size int) (*Cache[K, V], error)
  • func NewWithEvict[K comparable, V any](size int, onEvicted func(key K, value V)) (c *Cache[K, V], err error)
  • func (c *Cache[K, V]) Add(key K, value V) (evicted bool)
  • func (c *Cache[K, V]) Cap() int
  • func (c *Cache[K, V]) Contains(key K) bool
  • func (c *Cache[K, V]) ContainsOrAdd(key K, value V) (ok, evicted bool)
  • func (c *Cache[K, V]) Get(key K) (value V, ok bool)
  • func (c *Cache[K, V]) GetOldest() (key K, value V, ok bool)
  • func (c *Cache[K, V]) Keys() []K
  • func (c *Cache[K, V]) Len() int
  • func (c *Cache[K, V]) Peek(key K) (value V, ok bool)
  • func (c *Cache[K, V]) PeekOrAdd(key K, value V) (previous V, ok, evicted bool)
  • func (c *Cache[K, V]) Purge()
  • func (c *Cache[K, V]) Remove(key K) (present bool)
  • func (c *Cache[K, V]) RemoveOldest() (key K, value V, ok bool)
  • func (c *Cache[K, V]) Resize(size int) (evicted int)
  • func (c *Cache[K, V]) Values() []V

Constants

const (
	// DefaultEvictedBufferSize defines the default buffer size to store evicted key/val
	DefaultEvictedBufferSize = 16
)

Types

type Cache

type Cache[K comparable, V any] struct {
	// contains filtered or unexported fields
}

Cache is a thread-safe fixed size LRU cache.

func New

func New[K comparable, V any](size int) (*Cache[K, V], error)

New creates an LRU of the given size.

func NewWithEvict

func NewWithEvict[K comparable, V any](size int, onEvicted func(key K, value V)) (c *Cache[K, V], err error)

NewWithEvict constructs a fixed size cache with the given eviction callback.

func (*Cache[K, V]) Add

func (c *Cache[K, V]) Add(key K, value V) (evicted bool)

Add adds a value to the cache. Returns true if an eviction occurred.

func (*Cache[K, V]) Cap

func (c *Cache[K, V]) Cap() int

Cap returns the capacity of the cache

func (*Cache[K, V]) Contains

func (c *Cache[K, V]) Contains(key K) bool

Contains checks if a key is in the cache, without updating the recent-ness or deleting it for being stale.

func (*Cache[K, V]) ContainsOrAdd

func (c *Cache[K, V]) ContainsOrAdd(key K, value V) (ok, evicted bool)

ContainsOrAdd checks if a key is in the cache without updating the recent-ness or deleting it for being stale, and if not, adds the value. Returns whether found and whether an eviction occurred.

func (*Cache[K, V]) Get

func (c *Cache[K, V]) Get(key K) (value V, ok bool)

Get looks up a key's value from the cache.

func (*Cache[K, V]) GetOldest

func (c *Cache[K, V]) GetOldest() (key K, value V, ok bool)

GetOldest returns the oldest entry

func (*Cache[K, V]) Keys

func (c *Cache[K, V]) Keys() []K

Keys returns a slice of the keys in the cache, from oldest to newest.

func (*Cache[K, V]) Len

func (c *Cache[K, V]) Len() int

Len returns the number of items in the cache.

func (*Cache[K, V]) Peek

func (c *Cache[K, V]) Peek(key K) (value V, ok bool)

Peek returns the key value (or undefined if not found) without updating the "recently used"-ness of the key.

func (*Cache[K, V]) PeekOrAdd

func (c *Cache[K, V]) PeekOrAdd(key K, value V) (previous V, ok, evicted bool)

PeekOrAdd checks if a key is in the cache without updating the recent-ness or deleting it for being stale, and if not, adds the value. Returns whether found and whether an eviction occurred.

func (*Cache[K, V]) Purge

func (c *Cache[K, V]) Purge()

Purge is used to completely clear the cache.

func (*Cache[K, V]) Remove

func (c *Cache[K, V]) Remove(key K) (present bool)

Remove removes the provided key from the cache.

func (*Cache[K, V]) RemoveOldest

func (c *Cache[K, V]) RemoveOldest() (key K, value V, ok bool)

RemoveOldest removes the oldest item from the cache.

func (*Cache[K, V]) Resize

func (c *Cache[K, V]) Resize(size int) (evicted int)

Resize changes the cache size.

func (*Cache[K, V]) Values

func (c *Cache[K, V]) Values() []V

Values returns a slice of the values in the cache, from oldest to newest.