text: #ifndef dplyr_SummarisedVariable_H
  #define dplyr_SummarisedVariable_H
  
  namespace dplyr {
  
  class SummarisedVariable {
  public:
    SummarisedVariable(SEXP x) : data(x) {}
  
    inline operator SEXP() const {
      return data;
    }
  private:
    SEXP data;
  };
  
  }
  
  #endif
  