categories.html

---
layout: default
title: Categories
---

{% comment %}
Adapted from https://codinfox.github.io/dev/2015/03/06/use-tags-and-categories-in-your-jekyll-based-github-pages/
Possible license: https://creativecommons.org/licenses/by-nc/4.0/
{% endcomment %}

{% comment %}
=======================
The following part extracts all the tags from your posts and sort tags, so that you do not need to manually collect your tags to a place.
=======================
{% endcomment %}

{% assign rawcategories = "" %}
{% for post in site.posts %}
	{% assign tcategories = post.categories | join:'|' | append:'|' %}
	{% assign rawcategories = rawcategories | append:tcategories %}
{% endfor %}
{% assign rawcategories = rawcategories | split:'|' | sort %}

{% comment %}
=======================
The following part removes dulpicated tags and invalid tags like blank category.
=======================
{% endcomment %}
{% assign tags = "" %}
{% for category in rawcategories %}
	{% if category != "" %}
		{% if tags == "" %}
			{% assign tags = category | split:'|' %}
		{% endif %}
		{% unless tags contains category %}
			{% assign tags = tags | join:'|' | append:'|' | append:category | split:'|' %}
		{% endunless %}
	{% endif %}
{% endfor %}

<h2>Categories</h2>

{% comment %}
=======================
The purpose of this snippet is to list all the tags you have in your site.
=======================
{% endcomment %}
{% if tags.size > 0 %}
<p><ul class="tags">{% for category in tags %}<li><a href=#{{ category | slugify }}>{{ category }}</a></li>{% endfor %}</ul></p>
{% endif %}

{% comment %}
=======================
The purpose of this snippet is to list all your posts posted with a certain category.
=======================
{% endcomment %}
<div class="content">
{% for category in tags %}
	<h3 id="{{ category | slugify }}">{{ category }}</h3>
	<ul class="posts-by-tag">
	 {% for post in site.posts %}
		 {% if post.categories contains category %}
		 <li>
			<span class="post-title-by-tag"><a href="{% if site.baseurl == "/" %}{{ post.url }}{% else %}{{ post.url | prepend: site.baseurl }}{% endif %}">{%if post.header %}{{ post.header }}{% else %}{{ post.title }}{% endif %}</a></span>
			<time datetime="{{ post.date | date_to_xmlschema }}">{{ post.date | date: "%-d %B %Y" }}
				{% if post.last_modified_at %}
				<span> (last update on {{ post.last_modified_at | date: "%-d %B %Y" }})</span>
				{% endif %}
			</time>
			{% if post.categories.size > 0 %}
			{% endif %}
		 </li>
		 {% endif %}
	 {% endfor %}
	</ul>
{% endfor %}
</div>