code: public boolean contains(String name) {
          if (name == null) {
              throw new IllegalArgumentException("Other cannot be null");
          }
  
          if (this.name.equals(name)) {
              return true;
          }
  
          if (hasReferences()) {
              for (Marker ref : referenceList) {
                  if (ref.contains(name)) {
                      return true;
                  }
              }
          }
          return false;
      }
docs: This method is mainly used with Expression Evaluators.