@stdlib/assert/is-node-builtin/README.md

Standard assertion utilities.

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# isNodeBuiltin

> Test whether a string matches a Node.js built-in module name.

<section class="usage">

## Usage

```javascript
var isNodeBuiltin = require( '@stdlib/assert/is-node-builtin' );
```

#### isNodeBuiltin( value )

Tests whether a string matches a Node.js built-in module name.

```javascript
var bool = isNodeBuiltin( 'util' );
// returns true
```

</section>

<!-- /.usage -->

<section class="notes">

## Notes

-   For non-string values, the function returns `false`.

</section>

<!-- /.notes -->

<section class="examples">

## Examples

<!-- eslint no-undef: "error" -->

```javascript
var isNodeBuiltin = require( '@stdlib/assert/is-node-builtin' );

var out = isNodeBuiltin( 'fs' );
// returns true

out = isNodeBuiltin( 'child_process' );
// returns true

out = isNodeBuiltin( 'fs-extra' );
// returns false

out = isNodeBuiltin( 'moment' );
// returns false
```

</section>

<!-- /.examples -->

* * *

<section class="cli">

## CLI

<section class="usage">

### Usage

```text
Usage: is-node-builtin [options] [<string>]

Options:

  -h,    --help                Print this message.
  -V,    --version             Print the package version.
         --split sep           Delimiter for stdin data. Default: '/\\r?\\n/'.
```

</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">

### Notes

-   If the split separator is a [regular expression][mdn-regexp], ensure that the `split` option is either properly escaped or enclosed in quotes.

    ```bash
    # Not escaped...
    $ echo -n $'crypto\nndarray' | is-note-builtin --split /\r?\n/
    # Escaped...
    $ echo -n $'crypto\nndarray' | is-note-builtin --split /\\r?\\n/
    ```

-   The implementation ignores trailing delimiters.

</section>

<!-- /.notes -->

<section class="examples">

### Examples

```bash
$ is-node-builtin crypto
true
```

To use as a [standard stream][standard-streams],

```bash
$ echo -n 'crypto\ncluster\nfs-extra' | is-node-builtin
true
true
false
```

By default, when used as a [standard stream][standard-streams], the implementation assumes newline-delimited data. To specify an alternative delimiter, set the `split` option.

```bash
$ echo -n 'crypto\tbaz' | is-node-builtin --split '\t'
true
false
```

</section>

<!-- /.examples -->

</section>

<!-- /.cli -->

<!-- Section for related `stdlib` packages. Do not manually edit this section, as it is automatically populated. -->

<section class="related">

</section>

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<!-- Section for all links. Make sure to keep an empty line after the `section` element and another before the `/section` close. -->

<section class="links">

[standard-streams]: https://en.wikipedia.org/wiki/Standard_streams

[mdn-regexp]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Regular_Expressions

</section>

<!-- /.links -->