code: func Uglify(in string) string {
  	if path.Ext(in) == "" {
  		if len(in) < 2 {
  			return "/"
  		}
  		// /section/name/  -> /section/name.html
  		return path.Clean(in) + ".html"
  	}
  
  	name, ext := fileAndExt(in, pb)
  	if name == "index" {
  		// /section/name/index.html -> /section/name.html
  		d := path.Dir(in)
  		if len(d) > 1 {
  			return d + ext
  		}
  		return in
  	}
  	// /.xml -> /index.xml
  	if name == "" {
  		return path.Dir(in) + "index" + ext
  	}
  	// /section/name.html -> /section/name.html
  	return path.Clean(in)
  }
docs: // Uglify does the opposite of PrettifyURLPath().
  //     /section/name/index.html becomes /section/name.html
  //     /section/name/           becomes /section/name.html
  //     /section/name.html       becomes /section/name.html