func NewLRU[K comparable, V any](size int, onEvict EvictCallback[K, V], ttl time.Duration) *LRU[K, V] {
	if size < 0 {
		size = 0
	}
	if ttl <= 0 {
		ttl = noEvictionTTL
	}

	res := LRU[K, V]{
		ttl:       ttl,
		size:      size,
		evictList: NewList[K, V](),
		items:     make(map[K]*Entry[K, V]),
		onEvict:   onEvict,
		done:      make(chan struct{}),
	}

	// initialize the buckets