---
layout: "default"
title: "assertionFailure"
description: "Swift documentation for 'assertionFailure': Indicate that an internal sanity check failed."
keywords: "assertionFailure,func,swift,documentation"
root: "/v2.1"
---

<div class="declaration" id="func-assertionfailure_-string-file_-staticstring-line_-uint">
<a class="toggle-link" data-toggle="collapse" href="#comment-func-assertionfailure_-string-file_-staticstring-line_-uint">func assertionFailure(<wbr>_: (<wbr>) -&gt; String, file:<wbr> StaticStr