use where_exp filter to avoid Boolean template variable

Author: davidchambers

index.html

@@ -20,23 +20,21 @@ <h2>
         Upcoming Events
       </h2>
 
-      {% assign upcoming_events = false %}
+    {% assign upcoming_events = site.posts | where_exp: 'post', 'post.date >= site.time' %}
+    {% if upcoming_events.size == 0 %}
+      <p>There are no upcoming workshops.</p>
+    {% else %}
       <ul id="events-list">
-        {% for post in site.posts reversed %}
-          {% if post.date >= site.time %}
-            {% assign upcoming_events = true %}
-            <li>
-              <div class="background-image city" style="background-image: url({{ post.city_image_url }})"></div>
-              <div class="background-image organizer" style="background-image: url({{ post.organizer_image_url }})"></div>
-              <h3><a class="post-link" href="{{ post.url }}">{{ post.title }}</a></h3>
-              <p>{{ post.workshop_dates }}</li>
-            </li>
-          {% endif %}
-        {% endfor %}
+      {% for post in upcoming_events reversed %}
+        <li>
+          <div class="background-image city" style="background-image: url({{ post.city_image_url }})"></div>
+          <div class="background-image organizer" style="background-image: url({{ post.organizer_image_url }})"></div>
+          <h3><a class="post-link" href="{{ post.url }}">{{ post.title }}</a></h3>
+          <p>{{ post.workshop_dates }}</li>
+        </li>
+      {% endfor %}
       </ul>
-      {% unless upcoming_events %}
-        <p>There are no upcoming workshops.</p>
-      {% endunless %}
+    {% endif %}
 
     </div>
   </div>