hugoDocs/content/functions/findRe.md

title	linktitle	description	godocref	date	publishdate	lastmod	categories	tags	signature	workson	hugoversion	relatedfuncs	deprecated	aliases
findre	findRE	Returns a list of strings that match the regular expression.		2017-02-01	2017-02-01	2017-02-01	functions	regex					false

Returns a list of strings that match the regular expression. By default all matches will be included. The number of matches can be limitted with an optional third parameter.

The example below returns a list of all second level headers (<h2>) in the content:

{{ findRE "<h2.*?>(.|\n)*?</h2>" .Content }}

You can limit the number of matches in the list with a third parameter. The following example shows how to limit the returned value to just one match (or none, if there are no matched substrings):

{{ findRE "<h2.*?>(.|\n)*?</h2>" .Content 1 }}
    <!-- returns ["<h2 id="#foo">Foo</h2>"] -->

findRE Example: Building a Table of Contents

findRE allows us to build an automatically generated table of contents that could be used for a simple scrollspy if you don't want to use Hugo's native .TableOfContents feature. The following shows how this could be done in a partial template:

{{% code file="layouts/partials/toc.html" download="toc.html" %}}

{{ $headers := findRE "<h2.*?>(.|\n)*?</h2>" .Content }}
{{ if ge (len $headers) 1 }}
    <ul>
    {{ range $headers }}
        <li>
            <a href="#{{ . | plainify | urlize }}">
                {{ . | plainify }}
            </a>
        </li>
    {{ end }}
    </ul>
{{ end }}

{{% /code %}}

The preceding snippet tries to find all second-level headers and generate a list where at least one header is found. plainify strips the HTML and urlize converts the header into a valid URL.