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# Dirname

> [Regular expression][regexp] to capture a path [dirname][dirname].

<section class="usage">

## Usage

```javascript
var reDirname = require( '@stdlib/regexp/dirname' );
```

#### reDirname( \[platform] )

Returns a [regular expression][regexp] to capture a path [dirname][dirname].

```javascript
var RE = reDirname();
// returns <RegExp>

RE = reDirname( 'posix' );
// returns <RegExp>

var dir = RE.exec( '/foo/bar/index.js' )[ 1 ];
// returns '/foo/bar'

RE = reDirname( 'win32' );
// returns <RegExp>

dir = RE.exec( 'C:\\foo\\bar\\index.js' )[ 1 ];
// returns 'C:\\foo\\bar'
```

#### reBasename.REGEXP

[Regular expression][regexp] to capture a path dirname.

```javascript
var bool = ( reDirname.REGEXP.toString() === reDirname().toString() );
// returns true
```

#### reDirname.REGEXP_POSIX

[Regular expression][@stdlib/regexp/dirname-posix] to capture a [POSIX][posix] path dirname. 

```javascript
var dir = reDirname.REGEXP_POSIX.exec( '/foo/bar/index.js' )[ 1 ];
// returns '/foo/bar'
```

#### reDirname.REGEXP_WIN32

[Regular expression][@stdlib/regexp/dirname-windows] to capture a Windows path dirname. 

```javascript
var dir = reDirname.REGEXP_WIN32.exec( 'C:\\foo\\bar\\index.js' )[ 1 ];
// returns 'C:\\foo\\bar'
```

</section>

<!-- /.usage -->

<section class="notes">

## Notes

-   The as `REGEXP` exported [regular expression][regexp] is [platform][@stdlib/assert/is-windows]-dependent. If the current process is running on Windows, `REGEXP === REGEXP_WIN32`; otherwise, `REGEXP === REGEXP_POSIX`.

</section>

<!-- /.notes -->

<section class="examples">

## Examples

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

```javascript
var reDirname = require( '@stdlib/regexp/dirname' );
var RE_DIRNAME = reDirname();
var dir;

// Assuming a POSIX platform...
dir = RE_DIRNAME.exec( '/foo/bar/index.js' )[ 1 ];
// returns '/foo/bar'

dir = reDirname.REGEXP_POSIX.exec( '/foo/bar/home.html' )[ 1 ];
// returns '/foo/bar'

dir = reDirname.REGEXP_WIN32.exec( 'C:\\foo\\bar\\home.html' )[ 1 ];
// returns 'C:\\foo\\bar'
```

</section>

<!-- /.examples -->

<section class="links">

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

[dirname]: https://en.wikipedia.org/wiki/Dirname

[posix]: https://en.wikipedia.org/wiki/POSIX

[@stdlib/assert/is-windows]: https://www.npmjs.com/package/@stdlib/assert-is-windows

[@stdlib/regexp/dirname-posix]: https://www.npmjs.com/package/@stdlib/regexp/tree/main/dirname-posix

[@stdlib/regexp/dirname-windows]: https://www.npmjs.com/package/@stdlib/regexp/tree/main/dirname-windows

</section>

<!-- /.links -->