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