/**
 * LRU (Least Recently Used) cache implementation
 * Prevents unbounded memory growth in long-running processes
 */
/**
 * LRU cache with size limits to prevent unbounded memory growth
 *
 * This cache automatically evicts the least recently used entries when the
 * maximum size is reached. Essential for long-running processes that parse
 * multiple CSS files or work with large theme configurations.
 *
 * Time complexity:
 * - get: O(n) where n is cache size (linear scan for access order update)
 * - set: O(n) for eviction + access order update
 * - clear: O(1)
 *
 * @template TKey - Type of cache keys
 * @template TValue - Type of cached values
 *
 * @example
 * ```typescript
 * const cache = new LRUCache<string, number>(3);
 *
 * cache.set('a', 1);
 * cache.set('b', 2);
 * cache.set('c', 3);
 * cache.set('d', 4); // Evicts 'a' (least recently used)
 *
 * cache.get('a'); // undefined
 * cache.get('b'); // 2 (marks 'b' as recently used)
 * cache.size; // 3
 * ```
 */
export declare class LRUCache<TKey, TValue> {
    private readonly maxSize;
    private readonly cache;
    private accessOrder;
    /**
     * Creates a new LRU cache with the specified maximum size
     *
     * @param maxSize - Maximum number of entries to keep in cache
     */
    constructor(maxSize: number);
    /**
     * Retrieves a value from the cache and marks it as recently used
     *
     * @param key - Cache key to retrieve
     * @returns Cached value if exists, undefined otherwise
     */
    get(key: TKey): TValue | undefined;
    /**
     * Adds or updates a value in the cache
     *
     * If the cache is at maximum capacity and this is a new key,
     * the least recently used entry will be evicted.
     *
     * @param key - Cache key
     * @param value - Value to cache
     */
    set(key: TKey, value: TValue): void;
    /**
     * Removes all entries from the cache
     */
    clear(): void;
    /**
     * Gets the current number of entries in the cache
     *
     * @returns Number of cached entries
     */
    get size(): number;
}