/// <reference types="node" />
/// <reference types="node" />
/**
 * Common function for Stream
 * @desczh
 * Stream 常用函数
 * @file
 */
import { Readable, Stream } from 'stream';
import { Task } from 'fp-ts/Task';
/**
 * Returns a Buffer with data read from the stream.
 * @desczh
 * 读取流到Buffer
 * @since 0.2.0
 */
export declare function streamToBuffer(stream: Stream): Task<Buffer>;
/**
 * Determines whether the passed value is a `Stream`.
 * @desczh
 * 是否输入为`Stream`
 * @since 0.2.0
 */
export declare const isStream: (a: unknown) => a is Stream;
/**
 * Returns stream's size
 * @desczh
 * 获得流的长度
 * @since 0.2.0
 */
export declare function streamSize(stream: Stream): Task<number>;
/**
 * Returns a string with data read from the stream.
 * @desczh
 * 把流转换为文本
 * @since 0.2.0
 */
export declare const streamToString: ({ encoding }: {
    encoding?: BufferEncoding | undefined;
}) => (stream: Stream) => Task<string>;
/**
 * Returns a stream with text.
 * @desczh
 * 把文本转换为流
 * @since 0.2.2
 */
export declare const stringToStream: ({ encoding }: {
    encoding?: BufferEncoding | undefined;
}) => (a: string) => Stream;
/**
 * Reads a certain amount of bytes from the beginning of a Stream, returning a Buffer.
 * The amount of data read might be smaller if the stream ends before it could return the amount of data requested.
 *
 * If the `peek` argument is true, the data is put back into the beginning of the stream, so it can be consumed by another function
 *
 * Note that this function will pause the stream, so you might need to call the `resume` method on it to make it flow again.
 *
 * If passing a stream that has already ended, the function could enter into an infinite loop and return a Promise that never resolves. It's your responsibility to ensure that streams passed to this function still have data to return.
 *
 * @desczh
 * 从流的开始位置读取给定的长度的内容块
 * 如果peek为真,数据将放回到流中。
 *
 * @since 0.2.0
 */
export declare const readChunkFromStream: ({ size, peek }: {
    size: number;
    peek?: boolean | undefined;
}) => (stream: Readable) => Task<Buffer>;