include/wx/wxexpr.h

   1 /////////////////////////////////////////////////////////////////////////////
   2 // Name:        wxexpr.h
   3 // Purpose:     Prolog-like file I/O, used by resource system.
   4 // Author:      Julian Smart
   5 // Modified by:
   6 // Created:     01/02/97
   7 // RCS-ID:      $Id$
   8 // Copyright:   (c)
   9 // Licence:     wxWindows licence
  10 /////////////////////////////////////////////////////////////////////////////
  11
  12 #ifndef _WX_WXEXPRH__
  13 #define _WX_WXEXPRH__
  14
  15 #ifdef __GNUG__
  16 #pragma interface "wxexpr.h"
  17 #endif
  18
  19 #include <stdio.h>
  20
  21 #include "wx/defs.h"
  22 #include "wx/string.h"
  23
  24 #include "wx/ioswrap.h"
  25
  26 #include "wx/list.h"
  27 #include "wx/hash.h"
  28
  29 #include "wx/expr.h"
  30
  31 // Compatibility
  32 #define PrologExpr wxExpr
  33 #define PrologDatabase wxExprDatabase
  34 #define proioErrorHandler wxExprErrorHandler
  35 #define PROIO_ERROR_GENERAL 1
  36 #define PROIO_ERROR_SYNTAX  2
  37 #define PrologNull wxExprNull
  38 #define PrologInteger wxExprInteger
  39 #define PrologReal wxExprReal
  40 #define PrologWord wxExprWord
  41 #define PrologString wxExprString
  42 #define PrologList wxExprList
  43 #define PrologType wxExprType
  44
  45 // Error types
  46 #define WXEXPR_ERROR_GENERAL 1
  47 #define WXEXPR_ERROR_SYNTAX  2
  48
  49 // Error handler function definition. If app returns TRUE,
  50 // carry on processing.
  51 typedef bool (*wxExprErrorHandler) (int errorType, char *msg);
  52
  53 WXDLLEXPORT_DATA(extern wxExprErrorHandler) currentwxExprErrorHandler;
  54
  55 extern "C" WXDLLEXPORT_DATA(FILE*) yyin;
  56
  57 extern "C" WXDLLEXPORT int yyparse(void);
  58
  59 typedef enum {
  60     wxExprNull,
  61     wxExprInteger,
  62     wxExprReal,
  63     wxExprWord,
  64     wxExprString,
  65     wxExprList
  66 } wxExprType;
  67
  68 class WXDLLEXPORT wxExprDatabase;
  69
  70 class WXDLLEXPORT wxExpr
  71 {
  72  public:
  73   wxObject *client_data;
  74   wxExprType type;
  75   union {
  76     long integer;
  77     char *word;
  78     char *string;
  79     double real;
  80     wxExpr *first;  // If is a list expr, points to the first node
  81     } value;
  82
  83   wxExpr *next;     // If this is a node in a list, points to the next node
  84   wxExpr *last;     // If is a list expr, points to the last node
  85
  86   wxExpr(wxExprType the_type, char *word_or_string, bool allocate);
  87   wxExpr(const wxString& functor);      // Assume this is a new clause - pass functor
  88   wxExpr(wxExprType the_type, const wxString& word_or_string = "");
  89   wxExpr(long the_integer);
  90   wxExpr(double the_real);
  91   wxExpr(wxList *the_list);
  92   ~wxExpr(void);
  93
  94   inline wxExprType Type(void) const { return type; }
  95   inline long IntegerValue(void) const
  96   {
  97     if (type == wxExprInteger)
  98       return value.integer;
  99     else if (type == wxExprReal)
 100       return (long)value.real;
 101     else return 0;
 102   }
 103
 104   inline double RealValue(void) const {
 105     if (type == wxExprReal)
 106       return value.real;
 107     else if (type == wxExprInteger)
 108       return (double)value.integer;
 109     else return (double)0.0;
 110   }
 111
 112   inline wxString WordValue(void) const {
 113     if (type == wxExprWord)
 114       return value.word;
 115     else if (type == wxExprString)
 116       return wxString(value.string);
 117     else return wxString("");
 118   }
 119
 120   inline wxString StringValue(void) const {
 121     if (type == wxExprString)
 122       return wxString(value.string);
 123     else if (type == wxExprWord)
 124       return wxString(value.word);
 125     else return wxString("");
 126   }
 127
 128   // Get nth arg of clause (starting from 1)
 129   wxExpr *Arg(wxExprType type, int arg) const;
 130
 131   // Return nth argument of a list expression (starting from zero)
 132   wxExpr *Nth(int arg) const;
 133
 134   // Returns the number of elements in a list expression
 135   int Number(void) const;
 136
 137   // Make a clone
 138   wxExpr *Copy(void) const;
 139
 140   wxExpr *GetAttributeValueNode(const wxString& word) const;  // Use only for a clause or list
 141   wxExpr *AttributeValue(const wxString& word) const;  // Use only for a clause
 142   wxString Functor(void) const;                     // Only for a clause
 143   bool IsFunctor(const wxString& s) const;                     // Only for a clause
 144   void WriteClause(ostream& stream);  // Write this expression as a top-level clause
 145   void WriteExpr(ostream& stream);    // Write as any other subexpression
 146   void WriteLispExpr(ostream& stream);
 147
 148   // Append an expression to a list
 149   void Append(wxExpr *expr);
 150   // Insert at beginning of list
 151   void Insert(wxExpr *expr);
 152
 153   // Get first expr in list
 154   inline wxExpr *GetFirst(void) const { return ((type == wxExprList) ? value.first : (wxExpr*)NULL); }
 155
 156   // Get next expr if this is a node in a list
 157   inline wxExpr *GetNext(void) const { return next; }
 158
 159   // Get last expr in list
 160   inline wxExpr *GetLast(void) const { return ((type == wxExprList) ? last : (wxExpr*)NULL); }
 161
 162   // This should really be called SetAttributeValue since any existing
 163   // attribute-value is deleted first.
 164   void AddAttributeValue(const wxString& attribute, long value);
 165   void AddAttributeValue(const wxString& attribute, double value);
 166   void AddAttributeValueWord(const wxString& attribute, const wxString& value);
 167   void AddAttributeValueString(const wxString& attribute, const wxString& value);
 168   void AddAttributeValue(const wxString& attribute, wxList *value);
 169   void AddAttributeValue(const wxString& attribute, wxExpr *value);
 170   void AddAttributeValueStringList(const wxString& attribute, wxList *string_list);
 171
 172   void DeleteAttributeValue(const wxString& attribute);
 173
 174   bool GetAttributeValue(const wxString& att, int& var) const;
 175   bool GetAttributeValue(const wxString& att, long& var) const;
 176   bool GetAttributeValue(const wxString& att, float& var) const;
 177   bool GetAttributeValue(const wxString& att, double& var) const;
 178   bool GetAttributeValue(const wxString& att, wxString& var) const;  // Word OR string -> string
 179   bool GetAttributeValue(const wxString& att, wxExpr **var) const;
 180
 181   // Compatibility with old PrologIO
 182   inline void AssignAttributeValue(char *att, int *var) const { GetAttributeValue(att, *var); }
 183   inline void AssignAttributeValue(char *att, long *var) const { GetAttributeValue(att, *var); }
 184   inline void AssignAttributeValue(char *att, float *var) const { GetAttributeValue(att, *var); }
 185   inline void AssignAttributeValue(char *att, double *var) const { GetAttributeValue(att, *var); }
 186   inline void AssignAttributeValue(char *att, wxExpr **var) const { GetAttributeValue(att, var); }
 187   void AssignAttributeValue(char *att, char **var) const ;  // Word OR string -> string
 188
 189   // Add string items to list if the list attribute exists
 190   bool GetAttributeValueStringList(const wxString& att, wxList *var) const;
 191
 192   // Associate other data with this expression, e.g. when reading in a
 193   // number of linked items - store C++ object pointer with the expression
 194   // so we can index into the wxExpr database and fish out the pointer.
 195   inline void SetClientData(wxObject *data) { client_data = data; }
 196   inline wxObject *GetClientData(void) const { return client_data; }
 197 };
 198
 199 class WXDLLEXPORT wxExprDatabase: public wxList
 200 {
 201 private:
 202     wxNode *position;              // Where we are in a search
 203     wxHashTable *hash_table;
 204     wxString attribute_to_hash;
 205
 206 public:
 207     int noErrors;
 208
 209     wxExprDatabase(wxExprErrorHandler handler = 0);
 210
 211     // Use hashing on both the functor, and the attribute of
 212     // specified type (wxExprString or wxExprInteger) and name.
 213     // So to find node 45
 214     // (i.e. match the clause node(id=45, ...))
 215     // it usually requires 1 look-up: the keys for functor and attribute
 216     // are added together.
 217     // Obviously if the attribute was missing in a clause, it would
 218     // fail to be found by this method, but could be retrieved by a
 219     // linear search using BeginFind and FindClauseByFunctor,
 220     // or just searching through the list as per usual.
 221
 222     wxExprDatabase(wxExprType type, const wxString& attribute, int size = 500,
 223             wxExprErrorHandler handler = 0);
 224
 225     ~wxExprDatabase(void);
 226
 227     void BeginFind(void) ;          // Initialise a search
 228     wxExpr *FindClause(long id) ;  // Find a term based on an integer id attribute
 229     // e.g. node(id=23, type=rectangle, ....).
 230
 231     // Find on basis of attribute/value pairs, e.g. type=rectangle
 232     // This doesn't use hashing; it's a linear search.
 233     wxExpr *FindClause(const wxString& word, const wxString& value);
 234     wxExpr *FindClause(const wxString& word, long value);
 235     wxExpr *FindClause(const wxString& word, double value);
 236     wxExpr *FindClauseByFunctor(const wxString& functor);
 237
 238     wxExpr *HashFind(const wxString& functor, const wxString& value) const;
 239     wxExpr *HashFind(const wxString& functor, long value) const;
 240
 241     void Append(wxExpr *expr);  // Does cleverer things if hashing is on
 242     void ClearDatabase(void);
 243     inline int GetErrorCount() const { return noErrors; }
 244     bool Read(const wxString& filename);
 245     bool ReadFromString(const wxString& buffer);
 246     bool Write(const wxString& fileName);
 247     bool Write(ostream& stream);
 248     void WriteLisp(ostream& stream);
 249
 250     // Compatibility
 251     inline bool ReadProlog(char *filename) { return Read(wxString(filename)); }
 252     inline bool ReadPrologFromString(char *buffer) { return ReadFromString(wxString(buffer)); }
 253     inline void WriteProlog(ostream& stream) { Write(stream); }
 254
 255 private:
 256     DECLARE_DYNAMIC_CLASS(wxExprDatabase)
 257 };
 258
 259 // Function call-style interface - some more convenience wrappers/unwrappers
 260
 261 // Make a call
 262 WXDLLEXPORT wxExpr* wxExprMakeCall(const wxString& functor ...);
 263
 264 #define wxExprMakeInteger(x) (new wxExpr((long)x))
 265 #define wxExprMakeReal(x) (new wxExpr((double)x))
 266 #define wxExprMakeString(x) (new wxExpr(wxExprString, x))
 267 #define wxExprMakeWord(x)   (new wxExpr(wxExprWord, x))
 268 #define wxExprMake(x)       (new wxExpr(x))
 269
 270 // Checks functor
 271 WXDLLEXPORT bool wxExprIsFunctor(wxExpr *expr, const wxString& functor);
 272
 273 // Temporary variable for communicating between wxexpr.cpp and YACC/LEX
 274 WXDLLEXPORT_DATA(extern wxExprDatabase*) thewxExprDatabase;
 275
 276 // YACC/LEX can leave memory lying around...
 277 extern "C" WXDLLEXPORT int wxExprCleanUp();
 278
 279 #endif
 280