# prevGraphemeClusterBreak
> Return the previous extended grapheme cluster break in a string before a specified position.
## Usage
```javascript
var prevGraphemeClusterBreak = require( '@stdlib/string/prev-grapheme-cluster-break' );
```
#### prevGraphemeClusterBreak( string\[, fromIndex] )
Returns the previous extended grapheme cluster break in a string before a specified position.
```javascript
var out = prevGraphemeClusterBreak( 'last man standing' );
// returns 15
```
By default, the last extended grapheme cluster break in the string is returned. For the previous extended grapheme cluster break before a specified position in the string, provide a `fromIndex`.
```javascript
var out = prevGraphemeClusterBreak( 'last man standing', 4 );
// returns 3
```
## Notes
- If `string` is an empty string, the function returns `-1` irrespective of `fromIndex`.
- If there is no extended grapheme cluster break before `fromIndex`, the function returns `-1`.
- Note that `fromIndex` does **not** refer to a visual character position, but to an index in the ordered sequence of [UTF-16][utf-16] code units.
## Examples
```javascript
var prevGraphemeClusterBreak = require( '@stdlib/string/prev-grapheme-cluster-break' );
console.log( prevGraphemeClusterBreak( 'last man standing', 4 ) );
// => 3
console.log( prevGraphemeClusterBreak( 'presidential election', 8 ) );
// => 7
console.log( prevGraphemeClusterBreak( 'अनुच्छेद', 2 ) );
// => 0
console.log( prevGraphemeClusterBreak( '🌷', 1 ) );
// => -1
```
* * *
## CLI
### Usage
```text
Usage: prev-grapheme-cluster-break [options] []
Options:
-h, --help Print this message.
-V, --version Print the package version.
--fromIndex index Position in string. Default: string.length-1.
```
### Examples
```bash
$ prev-grapheme-cluster-break --fromIndex=2 अनुच्छेद
0
```
To use as a [standard stream][standard-streams],
```bash
$ echo -n 'अनुच्छेद' | prev-grapheme-cluster-break --fromIndex=2
0
```
[standard-streams]: https://en.wikipedia.org/wiki/Standard_streams
[utf-16]: https://en.wikipedia.org/wiki/UTF-16