---
layout: "default"
title: "FlattenCollectionIndex"
description: "Swift documentation for struct 'FlattenCollectionIndex'."
keywords: "FlattenCollectionIndex,struct,swift,documentation,advancedBy,advancedBy,distanceTo,successor"
root: "/v2.1"
---

<div class="intro-declaration"><code class="language-swift">struct FlattenCollectionIndex&lt;BaseElements : CollectionType where BaseElements.Generator.Element : CollectionType&gt;</code></div>


<table class="standard">
<tr>
<th id="inheritance">Inheritance</th