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