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