Sort by date in descending order in ruby in rails
<p>I would like to sort my list in a descending order by date which as a "New user list", in the database I have a column which is </p>

<pre><code>t.datetime "created_at",                                      null: false  
</code></pre>

<p>This is the time when a new user registered, in the view, I have the code like this:</p>

<pre><code>%table.table.table-striped.table-hover
      %thead
      %h3 New Users
      %hr
        %th Name
        %th Company
        %th Role
        %th Created date
        %th{:width =&gt; '50'}
        %th{:width =&gt; '50'}
        %th{:width =&gt; '50'}
      %tbody
      - @users.each do |user|
        -if user.role == "trial-member"
          - @created_at.sort{|a,b| b.created_at &lt;=&gt; a.created_at}.each do |created_at|
            %tr
            %td
              = user.first_name
              = user.last_name
            %td= user.company
            %td= user.role
            %td= user.created_at
            %td= link_to 'Approve', edit_user_path(user),  {:class =&gt; 'btn btn-success btn-sm'}
</code></pre>

<p>but this gives an error that "undefined method `sort' for nil:NilClass", what shall I do to sort the list in table descending by created date? Thank you.</p>