refactor: render fragment explicitly

Instead of including the template for non-hx-requests, inject the
rendered fragment.

src/main.rs

@@ -19,13 +19,12 @@ struct Fragment {
 #[derive(Default, Template)]
 #[template(path = "index.html")]
 struct Document {
-    // TODO: This is duplicated. Reuse the Fragment struct. But how?
-    users: Option<Vec<User>>,
+    fragment: Option<Fragment>,
 }
 
 #[get("/")]
 async fn index() -> actix_web::Result<impl Responder> {
-    let page = Document { users: None };
+    let page = Document { fragment: None };
     Ok(Html(page.render().expect("Valid template")))
 }
 
@@ -52,7 +51,8 @@ async fn users(req: HttpRequest) -> actix_web::Result<impl Responder> {
         }
         None => {
             // Render the whole document
-            Ok(Html(Document { users }.render().expect("Valid template")))
+            let fragment = Some(Fragment { users });
+            Ok(Html(Document { fragment }.render().expect("Valid template")))
         }
     }
 }

templates/index.html

@@ -6,14 +6,16 @@
         <p>A new old way to build web applications</p>
     </hgroup>
     <table>
-    {% if users.is_some() %}
-        {% include "fragment/user/table.html" %}
-    {% else %}
+
+    {% match fragment %}
+        {% when Some with (fragment) %}
+            {{ fragment|safe }}
+        {% when None %}
             <tr><td>
                 <button hx-get="/user" hx-target="table" hx-push-url="true">
                     Load data
                 </button>
             </td></tr>
-    {% endif %}
+    {% endmatch %}
     </table>
 {% endblock %}