> For the complete documentation index, see [llms.txt](https://docs.expression-library.bearstudios.co.uk/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.expression-library.bearstudios.co.uk/interface-overview/expression-functions.md).

# Expression Functions

![](https://2646749972-files.gitbook.io/~/files/v0/b/gitbook-legacy-files/o/assets%2F-LpXDHwnQxqNfdJjJA2-%2F-LqBuMaudgkrDwDV3N0Q%2F-LqC1YrbiFkouDbAfTt_%2Fadding%20functions.gif?alt=media\&token=32b2ea86-e8cf-42d8-bec9-6b2946c0b7c1)

This adds a neatly formatted expression library function comment onto your expression.

```javascript
/*

===expression.lib functions===
addMaster('masterName');
add3DPointControl('thisLayer/master','effectName',[value,value,value]);
add2DPointControl('thisLayer/master','effectName',[value,value]);

addColorControl('thisLayer/master','effectName','hexNumber');
addCheckboxControl('thisLayer/master','effectName',0/1);
addSliderControl('thisLayer/master','effectName',value);

addAngleControl('thisLayer/master','effectName',value);
addLayerControl('thisLayer/master','effectName');
===expression.lib end functions===

*/
```

If you already have an expression on the layer:

```javascript
var x = 100;
var y = 100;
[x,y]
```

It will keep that information and place the functions at the top of the expression.

```javascript
/*

===expression.lib functions===
addMaster('masterName');
add3DPointControl('thisLayer/master','effectName',[value,value,value]);
add2DPointControl('thisLayer/master','effectName',[value,value]);

addColorControl('thisLayer/master','effectName','hexNumber');
addCheckboxControl('thisLayer/master','effectName',0/1);
addSliderControl('thisLayer/master','effectName',value);

addAngleControl('thisLayer/master','effectName',value);
addLayerControl('thisLayer/master','effectName');
===expression.lib end functions===

*/
var x = 100;
var y = 100;
[x,y]
```

{% content-ref url="/pages/-Lq1h2ptJyrpnmEKVIe9" %}
[Adding Custom Controls](/adding-custom-controls.md)
{% endcontent-ref %}