active{{end}}" href="/values/">Values in file trees</a>
      <a class="sidebar-nav-item {{ispage tree-manipulation/*}}active{{end}}" href="/tree-manipulation/">Manipulating file trees</a>
      <a class="sidebar-nav-item {{ispage lazy-parallel/*}}active{{end}}" href="/lazy-parallel/">Laziness and parallelism</a>
      <a class="sidebar-nav-item {{ispage api/*}}active{{end}}" href="/api/">API documentation</a>
      <small>EXTRAS</small>
      <a class="sidebar-nav-item {{ispage metadata/*}}active{{end}}" h