/**
 * State flags shared by both stream sides and the duck-typing predicates that
 * `node:stream` exposes for classifying arbitrary values.
 * @module
 */
export declare const kIsDestroyed: unique symbol;
export declare const kIsErrored: unique symbol;
export declare const kIsReadable: unique symbol;
export declare const kIsWritable: unique symbol;
export declare const kIsDisturbed: unique symbol;
export declare const kState: unique symbol;
export declare const kOnConstructed: unique symbol;
export declare const kObjectMode: number;
export declare const kErrorEmitted: number;
export declare const kAutoDestroy: number;
export declare const kEmitClose: number;
export declare const kDestroyed: number;
export declare const kClosed: number;
export declare const kCloseEmitted: number;
export declare const kErrored: number;
export declare const kConstructed: number;
/** Whether `value` looks like a readable Node stream. `strict` additionally requires `pause`/`resume`. */
export declare function isReadableNodeStream(value: unknown, strict?: boolean): boolean;
export declare function isWritableNodeStream(value: unknown): boolean;
export declare function isDuplexNodeStream(value: unknown): boolean;
export declare function isNodeStream(value: unknown): boolean;
export declare function isReadableStream(value: unknown): value is ReadableStream;
export declare function isWritableStream(value: unknown): value is WritableStream;
export declare function isTransformStream(value: unknown): value is TransformStream;
export declare function isWebStream(value: unknown): boolean;
export declare function isIterable(value: unknown, isAsync?: boolean): boolean;
export declare function isDestroyed(stream: unknown): boolean | null;
/** Whether `end()` has been called. */
export declare function isWritableEnded(stream: unknown): boolean | null;
/** Whether `finish` has been emitted. With `strict === false`, an ended and drained stream counts. */
export declare function isWritableFinished(stream: unknown, strict?: boolean): boolean | null;
/** Whether `push(null)` has happened. */
export declare function isReadableEnded(stream: unknown): boolean | null;
/** Whether `end` has been emitted. With `strict === false`, an ended and drained stream counts. */
export declare function isReadableFinished(stream: unknown, strict?: boolean): boolean | null;
export declare function isReadable(stream: unknown): boolean | null;
export declare function isWritable(stream: unknown): boolean | null;
export declare function isFinished(stream: unknown, opts?: {
    readable?: boolean;
    writable?: boolean;
}): boolean | null;
export declare function isWritableErrored(stream: unknown): Error | null;
export declare function isReadableErrored(stream: unknown): Error | null;
export declare function isClosed(stream: unknown): boolean | null;
/** Whether `stream` is expected to emit `close` on its own, which `eos` relies on to decide what to wait for. */
export declare function willEmitClose(stream: unknown): boolean | null;
/** Whether anything has been read from `stream`. */
export declare function isDisturbed(stream: unknown): boolean;
export declare function isErrored(stream: unknown): boolean;
/** Read by `eos()` so `finished()` works on the web streams produced here. */
/** Set by `node:stream` on the web streams it creates; lets `finished()` observe one without consuming it. */
export declare const kIsClosedPromise: unique symbol;
export declare function trackClosed<T extends object>(stream: T, closed: Promise<void>): T;