---
title: ReadableWritablePair
url: https://www.fastly.com/documentation/reference/compute/sdks/javascript/js-compute/globals/interface.ReadableWritablePair/
---

**Kind:** Interface  
**Module:** [globals](https://www.fastly.com/documentation/reference/compute/sdks/javascript/js-compute/globals/)  
**Package:** @fastly/js-compute 4.0.1  
**Source:** https://github.com/fastly/js-compute-runtime/blob/70cf30af4e657879b2d1e7eafab880e39e3a3f7d/types/globals.d.ts#L1840

```javascript
interface ReadableWritablePair<R = any, W = any>
```

## Properties

### readable

**Type:** `ReadableStream<R>`  
**Source:** https://github.com/fastly/js-compute-runtime/blob/70cf30af4e657879b2d1e7eafab880e39e3a3f7d/types/globals.d.ts#L1841

### writable

**Type:** `WritableStream<W>`  
**Source:** https://github.com/fastly/js-compute-runtime/blob/70cf30af4e657879b2d1e7eafab880e39e3a3f7d/types/globals.d.ts#L1847

Provides a convenient, chainable way of piping this readable stream through a transform stream (or any other \{ writable, readable \} pair). It simply pipes the stream into the writable side of the supplied pair, and returns the readable side for further use.

Piping a stream will lock it for the duration of the pipe, preventing any other consumer from acquiring a reader.