#nav
  %a.home{:href => "/index"} ruby-x.org
  %a{:href => "index.html"} Abstract
  %a{:href => "toc.html"} Contents
  %a{:href => "ch1.html"} Chapter 1
  %a{:href => "ch2.html"} Chapter 2
  %a{:href => "ch3.html"} Chapter 3
  %a{:href => "ch4.html"} Chapter 4
  %a{:href => "ch5.html"} Chapter 5
  %a{:href => "ch6.html"} Chapter 6
  %a{:href => "ch7.html"} Chapter 7
  %a{:href => "ch8.html"} Chapter 8
  %a.here{:href => "bib.html"} Bibliography
  %a{:href => "app-A.html"} Appendix A
  %a{:href => "ack.html"} Acknowledgements