code: function showTooltipBind() {
                if(hasEnableExp && !scope.$eval(attrs[prefix+'Enable'])) {
                  return;
                }
  
                prepareTooltip();
  
                if ( ttScope.popupDelay ) {
                  // Do nothing if the tooltip was already scheduled to pop-up.
                  // This happens if show is triggered multiple times before any hide is triggered.
                  if (!popupTimeout) {
                    popupTimeout = $timeout( show, ttScope.popupDelay, false );
                    popupTimeout.then(function(reposition){reposition();});
                  }
                } else {
                  show()();
                }
              }
docs: Show the tooltip with delay if specified, otherwise show it immediately