type JsonCheck = {
    ok: true;
} | {
    ok: false;
    path: string;
    reason: string;
};
/** Precise "round-trips through JSON.stringify/parse unchanged" check for
 *  the stdlib `Json` type. Plain data only: class instances (Date, Map, ...)
 *  and non-finite numbers are rejected because stringify silently rewrites
 *  them; functions/undefined/symbols do not serialize at all; holes, extra
 *  array properties, symbol keys, and non-enumerable properties are rejected
 *  because stringify drops them. */
export declare function __isJsonValue(value: unknown): JsonCheck;
export {};