// Class Name: result
//
// Purpose:
//
//   The data flow object produced by an operation.  It is either a basic
//   element or a composite element.

#ifndef RESULT_CLASS
#define RESULT_CLASS

#include "characteristic_predicate.h"

class result : public characteristic_predicate
{
public:
  result();
  ~result();

  // type_name: the type of data contained in this result.  this can be either
  // "nil" (meaning a non-data result),
// "forward" (meaning it will be defined later), ??
  // or a type name listed in the ZENO table of elements.
  string type_name() const;
  void type_name(const string &name);

  // well_formed: returns TRUE if this result is currently well formed.
  // these parts of a well formed result are checked:
  //    1.  a type name is specified.
  //    2.  a result expression is specified.
  boolean well_formed() const;

  // pack: returns a packed form of the result, including the tree stating
  // the result's characteristic predicate.
//  virtual byte *pack(int &size) const;

  // this constructor recreates the result from a packed form.
//  friend result *result_unpack(byte *packed_form);

  // print: prints out the information associated with the result.
  virtual void print() const;

private:
  string my_type_name;
};

#endif