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




``` Hack
protected function buildTraits(
  Facebook\HackCodegen\HackBuilder $builder,
): void;
```




## Parameters




* [` Facebook\HackCodegen\HackBuilder `](<class.Facebook.HackCodegen.HackBuilder.md>)`` $builder ``




## Returns




- ` void `