<godepcop>
  <!-- The vdl package is very widely used; it is imported by most vdl-generated
       files, which are used throughout the codebase.

       Maintain a strict rule of no imports (other than standard packages),
       to avoid painful circular dependencies.  -->
  <pkg deny="..."/>

  <!-- Relax the rule for external tests -->
  <xtest allow="v.io/v23/..."/>
</godepcop>