---
layout: docs
title: render
id: trait.Facebook.HackCodegen.HackBuilderRenderer.render
docid: trait.Facebook.HackCodegen.HackBuilderRenderer.render
permalink: /docs/reference/trait.Facebook.HackCodegen.HackBuilderRenderer.render/
---
# Facebook\\HackCodegen\\HackBuilderRenderer::render()




``` Hack
final public function render(
  ?Facebook\HackCodegen\HackBuilder $builder = NULL,
): string;
```




## Parameters




+ ` ? `[` Facebook\HackCodegen\HackBuilder `](<class.Facebook.HackCodegen.HackBuilder.md>)`` $builder = NULL ``




## Returns




* ` string `