title: django javascript translation with simple interpolation
body: <p>The <a href="https://docs.djangoproject.com/en/dev/topics/i18n/translation/#using-the-javascript-translation-catalog" rel="nofollow noreferrer">documentation for javascript translation</a> in django only gives examples of pluralised interpolation. I want to do something simple like below:</p>
  <pre><code>var format = gettext(&quot;Displaying %(count)s / %(total)s&quot;)
  var text = interpolate(format, {&quot;count&quot;: 5, &quot;total&quot;: 10})
  </code></pre>
  <p>which should set <code>text</code> to <code>Displaying 5 / 10</code></p>
  <p>But this isn't working for me. I get <code>Displaying %(count)s / %(total)s</code> as the value for for <code>text</code>.</p>
  <p>Does anyone know how to do this simple sort of interpolation?</p>