text: /*****************************************************************************
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  * LLNL-CODE-442911
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  #ifndef SEQUENCE_H
  #define SEQUENCE_H
  #include <parser_exports.h>
  
  #include "Symbol.h"
  #include "SymbolSet.h"
  
  class Rule;
  
  // ****************************************************************************
  //  Class:  Sequence
  //
  //  Purpose:
  //    A series of terminals and nonterminals.  Used as the RHS of a
  //    production (Rule).
  //
  //  Programmer:  Jeremy Meredith
  //  Creation:    April  5, 2002
  //
  //  Modifications:
  //    Jeremy Meredith, Wed Nov  3 12:16:49 PST 2004
  //    Added prototypes before the friend declarations.
  //
  //    Brad Whitlock, Tue Jan 4 14:37:51 PST 2005
  //    Added API macros to the friend function declarations.
  //
  // ****************************************************************************
  
  // Some compilers (xlC) require prototypes before friend declarations
  class Sequence;
  PARSER_API Sequence operator+(const Symbol&, const Symbol&);
  PARSER_API Sequence operator+(const Sequence&, const Symbol&);
  
  class PARSER_API Sequence
  {
    public:
      Sequence();
      Sequence(const Sequence&);
      Sequence(const Symbol&);
  
      void AddSymbol(const Symbol&);
  
      int           Length()          const { return len;        }
      bool          Empty()           const { return len == 0;   }
      const Symbol *operator[](int i) const { return symbols[i]; }
  
      void Print(ostream &o, int pos = -1) const;
      bool operator==(const Sequence &s) const;
  
      bool          IsNullable(const std::vector<const Rule*> &rules) const;
      SymbolSet     GetFirstSet(const std::vector<const Rule*> &rules) const;
      Sequence      GetSubsequence(int pos) const;
      const Symbol *GetLastTerminal() const;
  
      friend PARSER_API Sequence operator+(const Symbol&, const Symbol&);
      friend PARSER_API Sequence operator+(const Sequence&, const Symbol&);
    protected:
      int len;
      std::vector<const Symbol*> symbols;
  };
  
  #endif
  