---
layout: docs
title: addGenericf
id: class.Facebook.HackCodegen.CodegenClassish.addGenericf
docid: class.Facebook.HackCodegen.CodegenClassish.addGenericf
permalink: /docs/reference/class.Facebook.HackCodegen.CodegenClassish.addGenericf/
---
# Facebook\\HackCodegen\\CodegenClassish::addGenericf()




Add a generic parameter using a %-placeholder format string




``` Hack
public function addGenericf(
  HH\Lib\Str\SprintfFormatString $format,
  mixed ...$args,
): this;
```




## Parameters




+ ` HH\Lib\Str\SprintfFormatString $format `
+ ` mixed ...$args `




## Returns




* ` this `