import Chunk from './chunk';
import VirtualOffset from './virtualOffset';
/**
 * Properly check if the given AbortSignal is aborted. Per the standard, if the
 * signal reads as aborted, this function throws either a DOMException
 * AbortError, or a regular error with a `code` attribute set to `ERR_ABORTED`.
 *
 * For convenience, passing `undefined` is a no-op
 *
 * @param {AbortSignal} [signal] an AbortSignal, or anything with an `aborted`
 * attribute
 *
 * @returns nothing
 */
export declare function checkAbortSignal(signal?: AbortSignal): void;
/**
 * Skips to the next tick, then runs `checkAbortSignal`.
 * Await this to inside an otherwise synchronous loop to
 * provide a place to break when an abort signal is received.
 * @param {AbortSignal} signal
 */
export declare function abortBreakPoint(signal?: AbortSignal): Promise<void>;
export declare function canMergeBlocks(chunk1: Chunk, chunk2: Chunk): boolean;
export declare function optimizeChunks(chunks: Chunk[], lowest?: VirtualOffset): Chunk[];