code: function lxStepNav()
      {
          return {
              restrict: 'E',
              require: ['lxStepNav', '^lxStepper'],
              templateUrl: 'step-nav.html',
              scope: {
                  activeIndex: '@lxActiveIndex',
                  step: '=lxStep'
              },
              link: link,
              controller: LxStepNavController,
              controllerAs: 'lxStepNav',
              bindToController: true,
              replace: true,
              transclude: false
          };
  
          function link(scope, element, attrs, ctrls)
          {
              ctrls[0].init(ctrls[1]);
          }
      }
docs: /* Step nav