hugo/content/functions/intersect.md

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title	linktitle	description	godocref	date	publishdate	lastmod	categories	tags	signature	workson	hugoversion	relatedfuncs	deprecated	aliases
intersect	intersect	Returns the common elements of two arrays or slices.		2017-02-01	2017-02-01	2017-02-01	functions						false

Given two arrays (or slices), intersect returns the common elements. The elements supported are strings, integers, and floats (only float64).

A useful example of intersect functionality is a "related posts" block. isset allows us to create a list of links to other posts that have tags that intersect with the tags in the current post.

The following is an example of a "related posts" partial template that could be added to a single page template:

{{% code file="layouts/partials/related-posts.html" download="related-posts.html" %}}

<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>

{{% /code %}}