time-to-botec/squiggle/node_modules/@stdlib/streams/node/empty/README.md

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@license Apache-2.0
Copyright (c) 2018 The Stdlib Authors.
Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
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# Empty Stream
> Create an "empty" [readable stream][readable-stream].
<section class="usage">
## Usage
```javascript
var emptyStream = require( '@stdlib/streams/node/empty' );
```
<a name="empty-stream"></a>
#### emptyStream( \[options] )
Returns an "empty" [readable stream][readable-stream] (i.e., a [stream][stream] which never streams any values).
```javascript
var inspectStream = require( '@stdlib/streams/node/inspect-sink' );
function log( chunk ) {
// This function should never be called...
console.log( chunk.toString() );
}
var stream = emptyStream();
var iStream = inspectStream( log );
stream.pipe( iStream );
```
The function accepts the following `options`:
- **objectMode**: specifies whether a [stream][stream] should operate in [objectMode][object-mode]. Default: `false`.
To set [stream][stream] `options`,
```javascript
var opts = {
'objectMode': true
};
var stream = emptyStream( opts );
```
* * *
#### emptyStream.factory( \[options] )
Returns a `function` for creating "empty" [readable streams][readable-stream].
```javascript
var opts = {
'objectMode': true
};
var createStream = emptyStream.factory( opts );
var stream1 = createStream();
var stream2 = createStream();
// ...
```
The method accepts the same `options` as [`emptyStream()`](#empty-stream).
* * *
#### emptyStream.objectMode()
This method is a convenience function to create "empty" [streams][stream] which **always** operate in [objectMode][object-mode].
```javascript
var inspectStream = require( '@stdlib/streams/node/inspect-sink' );
function log( v ) {
console.log( v );
}
var stream = emptyStream.objectMode();
var opts = {
'objectMode': true
};
var iStream = inspectStream( opts, log );
stream.pipe( iStream );
```
</section>
<!-- /.usage -->
<section class="notes">
</section>
<!-- /.notes -->
* * *
<section class="examples">
## Examples
<!-- eslint no-undef: "error" -->
```javascript
var inspectStream = require( '@stdlib/streams/node/inspect-sink' );
var emptyStream = require( '@stdlib/streams/node/empty' );
function log( v ) {
console.log( v.toString() );
}
var opts = {
'objectMode': true
};
var stream = emptyStream( opts );
opts = {
'objectMode': true
};
var iStream = inspectStream( opts, log );
stream.pipe( iStream );
```
</section>
<!-- /.examples -->
<!-- Section for describing a command-line interface. -->
* * *
<section class="cli">
## CLI
<!-- CLI usage documentation. -->
<section class="usage">
### Usage
```text
Usage: empty-stream [options]
Options:
-h, --help Print this message.
-V, --version Print the package version.
```
</section>
<!-- /.usage -->
<!-- CLI usage notes. Make sure to keep an empty line after the `section` element and another before the `/section` close. -->
<section class="notes">
</section>
<!-- /.notes -->
<!-- CLI usage examples. -->
<section class="examples">
### Examples
```bash
$ empty-stream
```
</section>
<!-- /.examples -->
</section>
<!-- /.cli -->
<section class="links">
[stream]: https://nodejs.org/api/stream.html
[object-mode]: https://nodejs.org/api/stream.html#stream_object_mode
[readable-stream]: https://nodejs.org/api/stream.html
</section>
<!-- /.links -->