title: Build less @import url dynamically
body: <p>While working on a google webfont import <strong>mixin</strong>, I noticed that it is not possible to build @import URLs dynamically.</p>
  
  <pre><code>.gFontImport (@name, @weights, @subsets) {
      @url: "http://fonts.googleapis.com/css?family=@{name}:@{weights}&amp;subset=@{subsets}";
      @import url(@url);
  }
  </code></pre>
  
  <p>Which can be narrowed down to </p>
  
  <pre><code>@url: "http://localhost/test.css";
  @import url(@url);
  </code></pre>
  
  <p>Neither any of these additional tests work:</p>
  
  <pre><code>@import url("@{url}"); // this one renders at least
  
  @import url(~"@{url}");
  </code></pre>
  
  <p>When the compiler renders the CSS file the @import URL is always left unchanged, e.g. <code>"@{url}"</code></p>