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# Filename

> [Regular expression][mdn-regexp] to split a filename.

<section class="usage">

## Usage

```javascript
var reFilename = require( '@stdlib/regexp/filename' );
```

#### reFilename( \[platform] )

Returns a [regular expression][mdn-regexp] to split a filename.

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

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

var parts = RE.exec( '/foo/bar/index.js' ).slice();
/* returns
    [
        '/foo/bar/index.js',  // input value
        '/',                  // root
        'foo/bar/',           // dirname
        'index.js',           // basename
        '.js'                 // extname
    ]
*/

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

parts = RE.exec( 'C:\\foo\\bar\\index.js' ).slice();
/* returns
    [
        'C:\\foo\\bar\\index.js',   // input value
        'C:',                       // device
        '\\',                       // slash
        'foo\\bar\\',               // dirname
        'index.js',                 // basename
        '.js'                       // extname
    ]
*/
```

#### reFilename.REGEXP

[Regular expression][mdn-regexp] to split a filename.

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

#### reFilename.REGEXP_POSIX

[Regular expression][@stdlib/regexp/filename-posix] to split a [POSIX][posix] filename. 

```javascript
var parts = reFilename.REGEXP_POSIX.exec( '/foo/bar/index.js' ).slice();
/* returns
    [
        '/foo/bar/index.js',  // input value
        '/',                  // root
        'foo/bar/',           // dirname
        'index.js',           // basename
        '.js'                 // extname
    ]
*/
```

#### reFilename.REGEXP_WIN32

[Regular expression][@stdlib/regexp/filename-windows] to split a Windows filename.

```javascript
var parts = reFilename.REGEXP_WIN32.exec( 'C:\\foo\\bar\\index.js' ).slice();
/* returns
    [
        'C:\\foo\\bar\\index.js',   // input value
        'C:',                       // device
        '\\',                       // slash
        'foo\\bar\\',               // dirname
        'index.js',                 // basename
        '.js'                       // extname
    ]
*/
```

</section>

<!-- /.usage -->

<section class="notes">

## Notes

-   The as `REGEXP` exported [regular expression][mdn-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 reFilename = require( '@stdlib/regexp/filename' );
var RE_FILENAME = reFilename();

// Assuming a POSIX platform...
var parts = RE_FILENAME.exec( '/foo/bar/index.js' ).slice();
/* returns
    [
        '/foo/bar/index.js',
        '/',
        'foo/bar/',
        'index.js',
        '.js'
    ]
*/

parts = reFilename.REGEXP_POSIX.exec( '/foo/bar/home.html' ).slice();
/* returns
    [
        '/foo/bar/home.html',
        '/',
        'foo/bar/',
        'home.html',
        '.html'
    ]
*/

parts = reFilename.REGEXP_WIN32.exec( 'C:\\foo\\bar\\home.html' ).slice();
/* returns
    [
        'C:\\foo\\bar\\home.html',
        'C:',
        '\\',
        'foo\\bar\\',
        'home.html',
        '.html'
    ]
*/
```

</section>

<!-- /.examples -->

<section class="links">

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

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

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

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

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

</section>

<!-- /.links -->