cache-entanglement/dist/types/utils/LRUMap.d.ts

Manage caches that are dependent on each other efficiently.

/**
 * Represents a node in the LRU cache's doubly linked list.
 * @template K Type of the key.
 * @template V Type of the value.
 */
export interface CacheNode<K, V> {
    key: K;
    value: V;
    prev: CacheNode<K, V> | null;
    next: CacheNode<K, V> | null;
}
/**
 * A Map-like data structure that implements the Least Recently Used (LRU) eviction policy.
 * Once the capacity is reached, the least recently accessed item is removed.
 * @template K Type of the key.
 * @template V Type of the value.
 */
export declare class LRUMap<K, V> {
    private capacity;
    private map;
    private head;
    private tail;
    /**
     * Creates an instance of LRUMap.
     * @param capacity The maximum number of items the cache can hold.
     */
    constructor(capacity: number);
    /**
     * Promotes a node to the head of the linked list (marks as most recently used).
     * @param node The node to promote.
     */
    private promote;
    /**
     * Disconnects a node from the doubly linked list.
     * @param node The node to extract.
     */
    private extract;
    /**
     * Inserts a node at the head of the doubly linked list.
     * @param node The node to prepend.
     */
    private prepend;
    /**
     * Stores or updates a value by key.
     * If the capacity is exceeded, the least recently used item (tail) is removed.
     * @param key The key to store.
     * @param value The value to store.
     */
    set(key: K, value: V): void;
    /**
     * Retrieves a value by key.
     * Accessing the item moves it to the "most recently used" position.
     * @param key The key to look for.
     * @returns The value associated with the key, or undefined if not found.
     */
    get(key: K): V | undefined;
    /**
     * Checks if a key exists in the cache without changing its access order.
     * @param key The key to check.
     * @returns True if the key exists, false otherwise.
     */
    has(key: K): boolean;
    /**
     * Removes a key and its associated value from the cache.
     * @param key The key to remove.
     * @returns True if the key was found and removed, false otherwise.
     */
    delete(key: K): boolean;
    /**
     * Returns an iterator of keys in the order of most recently used to least recently used.
     * @returns An iterable iterator of keys.
     */
    keys(): IterableIterator<K>;
    /**
     * Returns the current number of items in the cache.
     */
    get size(): number;
    /**
     * Clears all items from the cache.
     */
    clear(): void;
}