datum_id.h

   1 #ifndef _DATUM_ID_H_
   2 #define _DATUM_ID_H_
   3
   4 // datumで示される構文データの各ID
   5
   6 namespace utakata {
   7
   8     namespace syntax {
   9
  10         class DatumID
  11         {
  12         public:
  13             enum private_DATUMID_ {
  14                 STRING,               // <string>
  15                 ABBREVIATIONS,        // 各abbrev prefix
  16                 SYMBOL,               // <symbol>
  17                 NUMBER,               // <number>
  18                 CHARACTOR,            // <charactor>
  19                 BOOLEAN,              // <boolean>
  20                 BYTEVECTOR,           // <bytevector>
  21                 VECTOR,               // <vector>
  22                 LIST,                 // <list>
  23                 LITERAL,              // <lexeme datum>
  24                 NIL,
  25             };
  26
  27         private:
  28
  29             typedef private_DATUMID_ DATUMID_;
  30             DATUMID_ S_;
  31
  32             template<DATUMID_> class Literal;
  33
  34         public:
  35
  36             template<DATUMID_ S>
  37             DatumID(const Literal<S>&) : S_(S) {}
  38
  39             DATUMID_ toEnum() const {return S_;}
  40
  41             friend bool operator==(DatumID s, DatumID t) {return s.S_ == t.S_;}
  42             friend bool operator!=(DatumID s, DatumID t) {return !(s == t);}
  43
  44             static const Literal<STRING>           string;
  45             static const Literal<ABBREVIATIONS>    abbreviations;
  46             static const Literal<SYMBOL>           symbol;
  47             static const Literal<NUMBER>           number;
  48             static const Literal<CHARACTOR>        charactor;
  49             static const Literal<BOOLEAN>          boolean;
  50             static const Literal<BYTEVECTOR>       byteVector;
  51             static const Literal<VECTOR>           vector;
  52             static const Literal<LIST>             list;
  53             static const Literal<LITERAL>       literal;
  54             static const Literal<NIL>              nil;
  55         };
  56
  57         // 内部クラスかつ、単に該当するEnumを返すだけのクラステンプレート
  58         template<DatumID::private_DATUMID_ S>
  59         class DatumID::Literal : private DatumID
  60         {
  61         public:
  62
  63             DatumID::private_DATUMID_ toEnum() const {return S;}
  64
  65         private:
  66
  67             friend class DatumID;
  68             // 暗黙的なコピーコンストラクタを利用する。
  69             Literal() : DatumID(*this) {}
  70             ~Literal() {}
  71
  72             void* operator new(size_t);
  73             void operator delete(void*);
  74             void operator=(const Literal&);
  75             void* operator&() const;
  76         };
  77
  78     };
  79
  80 };
  81
  82 #endif /* _DATUM_ID_H_ */