import type { View } from "@perspective-dev/client";
/**
 * A single row's column values, keyed by column name. Numeric columns
 * yield a `number`; string (dictionary) columns yield the decoded
 * `string`; invalid (null) cells yield `null`.
 */
export type LazyRow = Map<string, string | number | null>;
/**
 * On-demand single-row fetcher backing lazy tooltip lookups. Given a
 * view row index, performs `view.with_typed_arrays({start_row, end_row:
 * start_row+1})` and projects the result into a plain `Map`. Concurrent
 * fetches for the same index are deduped into one Promise; resolved
 * rows are cached in a bounded LRU keyed by rowIdx.
 *
 * Invalidation is lifecycle-driven: the owning chart disposes and
 * constructs a new fetcher whenever its underlying view changes (i.e.
 * on each `draw`). In-flight fetches from the prior fetcher still
 * resolve, but callers stamp each fetch with a serial and discard
 * results whose serial no longer matches — so stale rows never reach
 * the tooltip. See the per-chart hover/pin paths for that plumbing.
 */
export declare class LazyRowFetcher {
    private _view;
    private _cache;
    private _inFlight;
    private readonly _maxCacheSize;
    constructor(view: View, maxCacheSize?: number);
    fetchRow(rowIdx: number): Promise<LazyRow>;
    private _fetch;
    dispose(): void;
    get isDisposed(): boolean;
}