docs: function ActivityScope(name, parent, seed) {
              _classCallCheck(this, ActivityScope);
  
              if (parent && !(parent instanceof ActivityScope)) {
                  throw new Error('parent must be an activity scope.');
              }
  
              if (seed && !(seed instanceof uuid)) {
                  throw new Error('seed must be a valid UUID.');
              }
  
              this.innerid = seed || new uuid();
              this.innername = name;
              this.innerparent = parent || null;
  
              activityTracker.start(this);
          }