title: style attribute expression value is not evaluated, yet src attribute is evaluated?
body: <p>What am I doing wrong here? (The literal object notation vs dot notation might not be relevant for my question. It's just me experimenting). </p>
  
  <pre><code>&lt;template lang="pug"&gt;
  - var medium_large = "obj.better_featured_image.media_details.sizes.medium_large.source_url";
  - var literalMedium = "obj['better_featured_image']['media_details']['sizes']['medium']['source_url']"
  
  #app
    div(v-for='(obj) in posts' :key='obj.index')
  
      // WORKS
      p {{obj.better_featured_image.id}}
      // out: 224
  
      // WORKS: - because of vue bind shorthand ":" :
      .feature(:src=literalMedium)
      .feature(:src=medium)
      // out: &lt;div data-v-ab895722="" src="/app/uploads/2018/06/9f6c2fdb-de2a-3351-b105-bd158ea6c890-300x150.jpg" class="feature"&gt;&lt;/div&gt;
  
      //ERROR  jshint: "unexpected token obj", (also tried without binding :style) atribute
      .feature(:style='background-image:url('+ {{obj.better_featured_image.source_url}} +');')
      .feature(:style='background-image:url('+ obj.better_featured_image.source_url +');')
  
  &lt;/template&gt;`
  </code></pre>