### Breaking

- Require Node.js 12.20  5831295
- This package is now pure ESM. Please [read this](https://gist.github.com/sindresorhus/a39789f98801d908bbc7ff3ecc99d99c).
- [Changed from a default export to named exports.](https://github.com/sindresorhus/is-stream/compare/sindresorhus:fb8caed...sindresorhus:6913e34#diff-5a831ea67cf5cf8703b0de46901ab25bd191f56b320053be9332d9a3b0d01d15L14-R42)

https://github.com/sindresorhus/is-stream/compare/v2.0.1...v3.0.0

sindresorhus

is-stream

# is-stream

> Check if something is a [Node.js stream](https://nodejs.org/api/stream.html)

## Install

```
$ npm install is-stream
```

## Usage

```js
import fs from 'node:fs';
import {isStream} from 'is-stream';

isStream(fs.createReadStream('unicorn.png'));
//=> true

isStream({});
//=> false
```

## API

### isStream(stream)

Returns a `boolean` for whether it's a [`Stream`](https://nodejs.org/api/stream.html#stream_stream).

#### isWritableStream(stream)

Returns a `boolean` for whether it's a [`stream.Writable`](https://nodejs.org/api/stream.html#stream_class_stream_writable).

#### isReadableStream(stream)

Returns a `boolean` for whether it's a [`stream.Readable`](https://nodejs.org/api/stream.html#stream_class_stream_readable).

#### isDuplexStream(stream)

Returns a `boolean` for whether it's a [`stream.Duplex`](https://nodejs.org/api/stream.html#stream_class_stream_duplex).

#### isTransformStream(stream)

Returns a `boolean` for whether it's a [`stream.Transform`](https://nodejs.org/api/stream.html#stream_class_stream_transform).

## Related

- [is-file-stream](https://github.com/jamestalmage/is-file-stream) - Detect if a stream is a file stream

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is-stream

Breaking

is-stream

Install

Usage

API

isStream(stream)

isWritableStream(stream)

isReadableStream(stream)

isDuplexStream(stream)

isTransformStream(stream)

Keywords

FAQs

What is is-stream?

Is is-stream popular?

Is is-stream well maintained?