interface FontTracerPoolOptions {
    taskTimeoutMs?: number;
}
interface StylesheetWithPredicates {
    text?: string;
    asset?: {
        text?: string;
    };
    predicates?: Record<string, unknown>;
}
interface TextByPropsEntry {
    text: string;
    props: Record<string, unknown>;
}
interface TraceOptions {
    signal?: AbortSignal;
}
declare class FontTracerPool {
    private _pool;
    private _taskTimeoutMs;
    constructor(numWorkers: number, { taskTimeoutMs }?: FontTracerPoolOptions);
    init(): Promise<void>;
    trace(htmlText: string, stylesheetsWithPredicates: StylesheetWithPredicates[], { signal }?: TraceOptions): Promise<TextByPropsEntry[]>;
    /**
     * Number of worker threads in the underlying piscina pool. Piscina
     * spawns up to minThreads === maxThreads at construction time, though
     * individual workers may still be loading their module when this is
     * read. Exposed primarily for tests.
     */
    get threadCount(): number;
    /**
     * Number of trace tasks waiting in the piscina queue (not yet dispatched
     * to a worker).
     */
    get queueSize(): number;
    destroy(): Promise<void>;
}
export = FontTracerPool;
//# sourceMappingURL=FontTracerPool.d.ts.map