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




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




## Parameters




- ` HH\Lib\Str\SprintfFormatString $condition `
- ` mixed ...$args `




## Returns




+ ` this `