# Documentation error or my error?

**URL:** <https://discourse.gohugo.io/t/documentation-error-or-my-error/7092>\
**Category:** support\
**Created:** [June 20, 2017, 6:33am UTC](https://discourse.gohugo.io/t/documentation-error-or-my-error/7092 "2017-06-20T06:33:57Z")\
**Posts on this page:** 1\
**Page:** 1

<div class="post-metadata">

**Author:** ![juh2](https://yyz2.discourse-cdn.com/flex036/user_avatar/discourse.gohugo.io/juh2/32/3980_2.png) [@juh2](https://discourse.gohugo.io/u/juh2)\
**Post date:** [June 20, 2017, 6:33am UTC](https://discourse.gohugo.io/t/documentation-error-or-my-error/7092/1 "2017-06-20T06:33:57Z")

</div>

This example is from [https://gohugo.io/templates/functions#intersect](https://gohugo.io/templates/functions#intersect)

```
<ul>
{{ $page_link := .Permalink }}
{{ $tags := .Params.tags }}
{{ range .Site.Pages }}
    {{ $page := . }}
    {{ $has_common_tags := intersect $tags .Params.tags | len | lt 0 }}
    {{ if and $has_common_tags (ne $page_link $page.Permalink) }}
        <li><a href="{{ $page.Permalink }}">{{ $page.Title }}</a></li>
    {{ end }}
{{ end }}
</ul>

```

Why has the len of the intersect be less than 0?  
I would think it should be greater than 0 if there is any intersect at all.