avoid extra COUNT queries for loaded Relations

app/views/hats/requests_index.html.erb

@@ -3,7 +3,7 @@
     Requested Hats
   </div>
 
-  <% if @hat_requests.count == 0 %>
+  <% if @hat_requests.length == 0 %>
     No hat requests.
   <% else %>
     <% @hat_requests.each_with_index do |hr,x| %>

app/views/home/_category.html.erb

@@ -0,0 +1,10 @@
+<div class="box">
+  Stories with <a href="/tags">tags</a> in the
+  <% @categories.each do |c| %>
+    <%= link_to c.category, category_path(c) %>
+  <% end %>
+  <%= "category".pluralize(@categories) %>
+
+  <%= render(partial: 'categories/multi_category_tip') if @categories.length == 1 %>
+</div>
+

app/views/invitations/index.html.erb

@@ -38,7 +38,7 @@
       <% end %>
     </tr>
   <% end %>
-  <% if @invitation_requests.count == 0 %>
+  <% if @invitation_requests.length == 0 %>
     <tr>
       <td colspan=<%= @user.is_moderator?? 5 : 4 %> align="center"><span
         class="na">No invitation requests</span></td>

app/views/replies/show.html.erb

@@ -30,7 +30,7 @@
   <p class="help">No replies to show.</p>
 <% end %>
 
-<% if @replies.count > RepliesController::REPLIES_PER_PAGE && @filter != 'unread'%>
+<% if @replies.length > RepliesController::REPLIES_PER_PAGE && @filter != 'unread'%>
 <div class="morelink">
   <% if @page && @page > 1 %>
     <a href="/replies<%= @page == 2 ? "" : "/page/#{@page - 1}" %>">&lt;&lt;