code: function activateNav(pos){
  		var offset = 100,
  		current, next, parent, isSub, hasSub;
  		win.unbind('hashchange', hashchange);
  		for(var i=sectionscount;i>0;i--){
  			if(sections[i-1].pos <= pos+offset){
  				navanchors.removeClass('current');
  				current = navanchors.eq(i-1);
  				current.addClass('current');
  				
  				parent = current.parent().parent();
  				next = current.next();
  				
  				hasSub = next.is('ul');
  				isSub = !parent.is('#documenter_nav');
  				
  				nav.find('ol:visible').not(parent).slideUp('fast');
  				if(isSub){
  					parent.prev().addClass('current');
  					parent.stop().slideDown('fast');
  				}else if(hasSub){
  					next.stop().slideDown('fast');
  				}
  				win.bind('hashchange', hashchange);
  				break;
  			};
  		}	
  	}
docs: activate current nav element