title: Pass Concatenated Variable and String as Argument to Template Helper
body: <p>If I try to pass a Variable and String as an argument to a template helper I end up with the string literal:</p>
  
  <pre><code>{{#ContainerSurface class='progressBarContainer {{namespace}}'}}
  </code></pre>
  
  <p>Ends up as <code>&lt;div class="famous-surface progressBarContainer {{namespace}}"&gt;</code></p>
  
  <p>If I try to do</p>
  
  <pre><code>{{#ContainerSurface class={{'progressBarContainer ' + namespace}}
  </code></pre>
  
  <p>I end up with error:</p>
  
  <blockquote>
    <p>=> Errors prevented startup:</p>
    
    <p>While building the application:
       client/cordova/pages/widgets/progressBar/progressBar.html:2: Expected identifier, number,
       string, boolean, or null
       ...sBarContainer' class={{'progressBarContai...
       ^</p>
    
    <p>=> Your application has errors. Waiting for file change.</p>
  </blockquote>
  
  <p>I can make a Template Helper that returns the String + Variable, but that makes for messy code as I need to do this more than once.</p>