code: function onWhichEvent(sense, name, nbFinger) {
          var prefix = 'Short';
          if (sense.hasPaused) prefix = 'Long';
          var onEventName = 'on' + prefix + name + nbFinger;
          if (a4p.isDefined(sense[onEventName]) && (sense[onEventName] != null)) {
              return onEventName;
          }
          if (sense.options.prefixPriority) {
              // the 'Short'/'Long' prefix has priority over the number of fingers  : sense-long-tap before sense-tap-2
              onEventName = 'on' + prefix + name;
              if (a4p.isDefined(sense[onEventName]) && (sense[onEventName] != null)) {
                  return onEventName;
              }
              onEventName = 'on' + name + nbFinger;
              if (a4p.isDefined(sense[onEventName]) && (sense[onEventName] != null)) {
                  return onEventName;
              }
          } else {
              // the number of fingers has priority over the 'Short'/'Long' prefix  : sense-tap-2 before sense-long-tap
              onEventName = 'on' + name + nbFinger;
              if (a4p.isDefined(sense[onEventName]) && (sense[onEventName] != null)) {
                  return onEventName;
              }
              onEventName = 'on' + prefix + name;
              if (a4p.isDefined(sense[onEventName]) && (sense[onEventName] != null)) {
                  return onEventName;
              }
          }
          onEventName = 'on' + name;
          if (a4p.isDefined(sense[onEventName]) && (sense[onEventName] != null)) {
              return onEventName;
          }
          return '';
      }
docs: Gesture events utilities