/**
 * The operation a request expects a reply for. The host answers a transform
 * request (`{"file":...}`) with `{"typescript":...,"found":...}` and an update
 * request (`{"update":...,"content":...}`) with `{"updated":...}`. The client
 * knows which it sent, so it validates the reply's shape against the operation
 * before handing it back — a well-formed JSON object of the wrong operation
 * shape is a protocol error, not a valid negative result.
 */
export type ResidentReplyKind = "transform" | "update";
/** Options for spawning the resident transform host. */
export interface ResidentTransformProcessOptions {
    args: readonly string[];
    binary: string;
    cwd?: string;
    env?: NodeJS.ProcessEnv;
}
/** Per-request lifecycle controls for a resident transform host. */
export interface ResidentTransformRequestOptions {
    /** Abort this request. An in-flight abort retires the FIFO host. */
    signal?: AbortSignal;
}
/**
 * Async client for the long-lived `utility-host serve` process.
 *
 * The host transforms the whole project once at startup, caches every file's
 * transformed TypeScript, then answers newline-delimited requests. This class
 * speaks that protocol: each {@link request} writes one JSON line and the host
 * replies with one line, matched FIFO. A transform request (`{"file":...}`) is
 * answered with `{"typescript":...,"found":...}`, and an update request
 * (`{"update":...,"content":...}`) with `{"updated":...}`.
 *
 * One resident process answers every request from one service instead of
 * spawning a fresh `transform` subprocess per call, so a single process pays
 * the project compile once (samchon/ttsc#255).
 */
export declare class ResidentTransformProcess {
    private readonly child;
    private readonly reader;
    private readonly pending;
    private stderr;
    private failure;
    constructor(options: ResidentTransformProcessOptions);
    /**
     * Send one request to the host and resolve with its validated JSON reply. The
     * host answers in FIFO order; `kind` tells the client which reply shape the
     * payload asks for, so the reply is validated as a well-formed `kind` reply
     * before it resolves. Rejects when the reply is not a valid `kind` reply,
     * when the host has already failed or exited, or if writing the request
     * fails.
     */
    request(payload: Record<string, unknown>, kind: ResidentReplyKind, options?: ResidentTransformRequestOptions): Promise<Record<string, unknown>>;
    /**
     * Terminate the resident process and reject any in-flight requests. Safe to
     * call more than once.
     */
    dispose(): void;
    private onLine;
    private onReaderClose;
    private fail;
    private rejectAll;
    private settlePending;
    private cancel;
    private terminate;
    private exitError;
}