include/wx/any.h

   1 /////////////////////////////////////////////////////////////////////////////
   2 // Name:        wx/any.h
   3 // Purpose:     wxAny class
   4 // Author:      Jaakko Salli
   5 // Modified by:
   6 // Created:     07/05/2009
   7 // RCS-ID:      $Id$
   8 // Copyright:   (c) wxWidgets team
   9 // Licence:     wxWindows licence
  10 /////////////////////////////////////////////////////////////////////////////
  11
  12 #ifndef _WX_ANY_H_
  13 #define _WX_ANY_H_
  14
  15 #include "wx/defs.h"
  16
  17 #if wxUSE_ANY
  18
  19 #include <new> // for placement new
  20 #include "wx/string.h"
  21 #include "wx/meta/if.h"
  22 #include "wx/typeinfo.h"
  23 #include "wx/list.h"
  24
  25 // Size of the wxAny value buffer.
  26 enum
  27 {
  28     WX_ANY_VALUE_BUFFER_SIZE = 16
  29 };
  30
  31 union wxAnyValueBuffer
  32 {
  33     union Alignment
  34     {
  35     #if wxHAS_INT64
  36         wxInt64 m_int64;
  37     #endif
  38         long double m_longDouble;
  39         void ( *m_funcPtr )(void);
  40         void ( wxAnyValueBuffer::*m_mFuncPtr )(void);
  41     } m_alignment;
  42
  43     void*   m_ptr;
  44     wxByte  m_buffer[WX_ANY_VALUE_BUFFER_SIZE];
  45 };
  46
  47 //
  48 // wxAnyValueType is base class for value type functionality for C++ data
  49 // types used with wxAny. Usually the default template (wxAnyValueTypeImpl<>)
  50 // will create a satisfactory wxAnyValueType implementation for a data type.
  51 //
  52 class WXDLLIMPEXP_BASE wxAnyValueType
  53 {
  54     WX_DECLARE_ABSTRACT_TYPEINFO(wxAnyValueType)
  55 public:
  56     /**
  57         Default constructor.
  58     */
  59     wxAnyValueType()
  60     {
  61     }
  62
  63     /**
  64         Destructor.
  65     */
  66     virtual ~wxAnyValueType()
  67     {
  68     }
  69
  70     /**
  71         This function is used for internal type matching.
  72     */
  73     virtual bool IsSameType(const wxAnyValueType* otherType) const = 0;
  74
  75     /**
  76         This function is called every time the data in wxAny
  77         buffer needs to be freed.
  78     */
  79     virtual void DeleteValue(wxAnyValueBuffer& buf) const = 0;
  80
  81     /**
  82         Implement this for buffer-to-buffer copy.
  83
  84         @param src
  85             This is the source data buffer.
  86
  87         @param dst
  88             This is the destination data buffer that is in either
  89             uninitialized or freed state.
  90     */
  91     virtual void CopyBuffer(const wxAnyValueBuffer& src,
  92                             wxAnyValueBuffer& dst) const = 0;
  93
  94     /**
  95         Convert value into buffer of different type. Return false if
  96         not possible.
  97     */
  98     virtual bool ConvertValue(const wxAnyValueBuffer& src,
  99                               wxAnyValueType* dstType,
 100                               wxAnyValueBuffer& dst) const = 0;
 101
 102     /**
 103         Use this template function for checking if wxAnyValueType represents
 104         a specific C++ data type.
 105
 106         @remarks This template function does not work on some older compilers
 107                 (such as Visual C++ 6.0). For full compiler compatibility
 108                 please use wxANY_VALUE_TYPE_CHECK_TYPE(valueTypePtr, T) macro
 109                 instead.
 110
 111         @see wxAny::CheckType()
 112     */
 113     // FIXME-VC6: remove this hack when VC6 is no longer supported
 114     template <typename T>
 115     bool CheckType(T* reserved = NULL) const;
 116
 117 #if wxUSE_EXTENDED_RTTI
 118     virtual const wxTypeInfo* GetTypeInfo() const = 0;
 119 #endif
 120 private:
 121 };
 122
 123
 124 //
 125 // We need to allocate wxAnyValueType instances in heap, and need to use
 126 // scoped ptr to properly deallocate them in dynamic library use cases.
 127 // Here we have a minimal specialized scoped ptr implementation to deal
 128 // with various compiler-specific problems with template class' static
 129 // member variable of template type with explicit constructor which
 130 // is initialized in global scope.
 131 //
 132 class wxAnyValueTypeScopedPtr
 133 {
 134 public:
 135     wxAnyValueTypeScopedPtr(wxAnyValueType* ptr) : m_ptr(ptr) { }
 136     ~wxAnyValueTypeScopedPtr() { delete m_ptr; }
 137     wxAnyValueType* get() const { return m_ptr; }
 138 private:
 139     wxAnyValueType* m_ptr;
 140 };
 141
 142
 143 //
 144 // This method of checking the type is compatible with VC6
 145 #define wxANY_VALUE_TYPE_CHECK_TYPE(valueTypePtr, T) \
 146     wxAnyValueTypeImpl<T>::IsSameClass(valueTypePtr)
 147
 148
 149 /**
 150     Helper macro for defining user value types.
 151
 152     Even though C++ RTTI would be fully available to use, we'd have to to
 153     facilitate sub-type system which allows, for instance, wxAny with
 154     signed short '15' to be treated equal to wxAny with signed long long '15'.
 155     Having sm_instance is important here.
 156
 157     NB: We really need to have wxAnyValueType instances allocated
 158         in heap. They are stored as static template member variables,
 159         and with them we just can't be too careful (eg. not allocating
 160         them in heap broke the type identification in GCC).
 161 */
 162 #define WX_DECLARE_ANY_VALUE_TYPE(CLS) \
 163     friend class wxAny; \
 164     WX_DECLARE_TYPEINFO_INLINE(CLS) \
 165 public: \
 166     static bool IsSameClass(const wxAnyValueType* otherType) \
 167     { \
 168         return wxTypeId(*sm_instance.get()) == wxTypeId(*otherType); \
 169     } \
 170     virtual bool IsSameType(const wxAnyValueType* otherType) const \
 171     { \
 172         return IsSameClass(otherType); \
 173     } \
 174 private: \
 175     static wxAnyValueTypeScopedPtr sm_instance; \
 176 public: \
 177     static wxAnyValueType* GetInstance() \
 178     { \
 179         return sm_instance.get(); \
 180     }
 181
 182
 183 #define WX_IMPLEMENT_ANY_VALUE_TYPE(CLS) \
 184 wxAnyValueTypeScopedPtr CLS::sm_instance(new CLS());
 185
 186
 187 #ifdef __VISUALC6__
 188     // "non dll-interface class 'xxx' used as base interface
 189     #pragma warning (push)
 190     #pragma warning (disable:4275)
 191 #endif
 192
 193 /**
 194     Following are helper classes for the wxAnyValueTypeImplBase.
 195 */
 196 namespace wxPrivate
 197 {
 198
 199 template<typename T>
 200 class wxAnyValueTypeOpsInplace
 201 {
 202 public:
 203     static void DeleteValue(wxAnyValueBuffer& buf)
 204     {
 205         T* value = reinterpret_cast<T*>(&buf.m_buffer[0]);
 206         value->~T();
 207
 208         // Some compiler may given 'unused variable' warnings without this
 209         wxUnusedVar(value);
 210     }
 211
 212     static void SetValue(const T& value,
 213                          wxAnyValueBuffer& buf)
 214     {
 215         // Use placement new
 216         void* const place = buf.m_buffer;
 217         ::new(place) T(value);
 218     }
 219
 220     static const T& GetValue(const wxAnyValueBuffer& buf)
 221     {
 222         // Breaking this code into two lines should suppress
 223         // GCC's 'type-punned pointer will break strict-aliasing rules'
 224         // warning.
 225         const T* value = reinterpret_cast<const T*>(&buf.m_buffer[0]);
 226         return *value;
 227     }
 228 };
 229
 230
 231 template<typename T>
 232 class wxAnyValueTypeOpsGeneric
 233 {
 234 public:
 235     template<typename T2>
 236     class DataHolder
 237     {
 238     public:
 239         DataHolder(const T2& value)
 240         {
 241             m_value = value;
 242         }
 243         virtual ~DataHolder() { }
 244
 245         T2   m_value;
 246     private:
 247         wxDECLARE_NO_COPY_CLASS(DataHolder);
 248     };
 249
 250     static void DeleteValue(wxAnyValueBuffer& buf)
 251     {
 252         DataHolder<T>* holder = static_cast<DataHolder<T>*>(buf.m_ptr);
 253         delete holder;
 254     }
 255
 256     static void SetValue(const T& value,
 257                          wxAnyValueBuffer& buf)
 258     {
 259         DataHolder<T>* holder = new DataHolder<T>(value);
 260         buf.m_ptr = holder;
 261     }
 262
 263     static const T& GetValue(const wxAnyValueBuffer& buf)
 264     {
 265         DataHolder<T>* holder = static_cast<DataHolder<T>*>(buf.m_ptr);
 266         return holder->m_value;
 267     }
 268 };
 269
 270 } // namespace wxPrivate
 271
 272
 273 /**
 274     Intermediate template for the generic value type implementation.
 275     We can derive from this same value type for multiple actual types
 276     (for instance, we can have wxAnyValueTypeImplInt for all signed
 277     integer types), and also easily implement specialized templates
 278     with specific dynamic type conversion.
 279 */
 280 template<typename T>
 281 class wxAnyValueTypeImplBase : public wxAnyValueType
 282 {
 283     typedef typename wxIf< sizeof(T) <= WX_ANY_VALUE_BUFFER_SIZE,
 284                            wxPrivate::wxAnyValueTypeOpsInplace<T>,
 285                            wxPrivate::wxAnyValueTypeOpsGeneric<T> >::value
 286             Ops;
 287
 288 public:
 289     wxAnyValueTypeImplBase() : wxAnyValueType() { }
 290     virtual ~wxAnyValueTypeImplBase() { }
 291
 292     virtual void DeleteValue(wxAnyValueBuffer& buf) const
 293     {
 294         Ops::DeleteValue(buf);
 295     }
 296
 297     virtual void CopyBuffer(const wxAnyValueBuffer& src,
 298                             wxAnyValueBuffer& dst) const
 299     {
 300         Ops::SetValue(Ops::GetValue(src), dst);
 301     }
 302
 303     /**
 304         It is important to reimplement this in any specialized template
 305         classes that inherit from wxAnyValueTypeImplBase.
 306     */
 307     static void SetValue(const T& value,
 308                          wxAnyValueBuffer& buf)
 309     {
 310         Ops::SetValue(value, buf);
 311     }
 312
 313     /**
 314         It is important to reimplement this in any specialized template
 315         classes that inherit from wxAnyValueTypeImplBase.
 316     */
 317     static const T& GetValue(const wxAnyValueBuffer& buf)
 318     {
 319         return Ops::GetValue(buf);
 320     }
 321 #if wxUSE_EXTENDED_RTTI
 322     virtual const wxTypeInfo* GetTypeInfo() const
 323     {
 324         return wxGetTypeInfo((T*)NULL);
 325     }
 326 #endif
 327 };
 328
 329
 330 /*
 331     Generic value type template. Note that bulk of the implementation
 332     resides in wxAnyValueTypeImplBase.
 333 */
 334 template<typename T>
 335 class wxAnyValueTypeImpl : public wxAnyValueTypeImplBase<T>
 336 {
 337     WX_DECLARE_ANY_VALUE_TYPE(wxAnyValueTypeImpl<T>)
 338 public:
 339     wxAnyValueTypeImpl() : wxAnyValueTypeImplBase<T>() { }
 340     virtual ~wxAnyValueTypeImpl() { }
 341
 342     virtual bool ConvertValue(const wxAnyValueBuffer& src,
 343                               wxAnyValueType* dstType,
 344                               wxAnyValueBuffer& dst) const
 345     {
 346         wxUnusedVar(src);
 347         wxUnusedVar(dstType);
 348         wxUnusedVar(dst);
 349         return false;
 350     }
 351 };
 352
 353 template<typename T>
 354 wxAnyValueTypeScopedPtr wxAnyValueTypeImpl<T>::sm_instance = new wxAnyValueTypeImpl<T>();
 355
 356
 357 //
 358 // Helper macro for using same base value type implementation for multiple
 359 // actual C++ data types.
 360 //
 361 #define _WX_ANY_DEFINE_SUB_TYPE(T, CLSTYPE) \
 362 template<> \
 363 class wxAnyValueTypeImpl<T> : public wxAnyValueTypeImpl##CLSTYPE \
 364 { \
 365     typedef wxAnyBase##CLSTYPE##Type UseDataType; \
 366 public: \
 367     wxAnyValueTypeImpl() : wxAnyValueTypeImpl##CLSTYPE() { } \
 368     virtual ~wxAnyValueTypeImpl() { } \
 369     static void SetValue(const T& value, wxAnyValueBuffer& buf) \
 370     { \
 371         void* voidPtr = reinterpret_cast<void*>(&buf.m_buffer[0]); \
 372         UseDataType* dptr = reinterpret_cast<UseDataType*>(voidPtr); \
 373         *dptr = static_cast<UseDataType>(value); \
 374     } \
 375     static T GetValue(const wxAnyValueBuffer& buf) \
 376     { \
 377         const void* voidPtr = \
 378             reinterpret_cast<const void*>(&buf.m_buffer[0]); \
 379         const UseDataType* sptr = \
 380             reinterpret_cast<const UseDataType*>(voidPtr); \
 381         return static_cast<T>(*sptr); \
 382     }
 383
 384 #if wxUSE_EXTENDED_RTTI
 385 #define WX_ANY_DEFINE_SUB_TYPE(T, CLSTYPE) \
 386 _WX_ANY_DEFINE_SUB_TYPE(T, CLSTYPE)\
 387     virtual const wxTypeInfo* GetTypeInfo() const  \
 388     { \
 389         return wxGetTypeInfo((T*)NULL); \
 390     } \
 391 };
 392 #else
 393 #define WX_ANY_DEFINE_SUB_TYPE(T, CLSTYPE) \
 394 _WX_ANY_DEFINE_SUB_TYPE(T, CLSTYPE)\
 395 };
 396 #endif
 397
 398 //
 399 //  Integer value types
 400 //
 401
 402 #ifdef wxLongLong_t
 403     typedef wxLongLong_t wxAnyBaseIntType;
 404     typedef wxULongLong_t wxAnyBaseUintType;
 405 #else
 406     typedef long wxAnyBaseIntType;
 407     typedef unsigned long wxAnyBaseUintType;
 408 #endif
 409
 410
 411 class WXDLLIMPEXP_BASE wxAnyValueTypeImplInt :
 412     public wxAnyValueTypeImplBase<wxAnyBaseIntType>
 413 {
 414     WX_DECLARE_ANY_VALUE_TYPE(wxAnyValueTypeImplInt)
 415 public:
 416     wxAnyValueTypeImplInt() :
 417         wxAnyValueTypeImplBase<wxAnyBaseIntType>() { }
 418     virtual ~wxAnyValueTypeImplInt() { }
 419
 420     virtual bool ConvertValue(const wxAnyValueBuffer& src,
 421                               wxAnyValueType* dstType,
 422                               wxAnyValueBuffer& dst) const;
 423 };
 424
 425
 426 class WXDLLIMPEXP_BASE wxAnyValueTypeImplUint :
 427     public wxAnyValueTypeImplBase<wxAnyBaseUintType>
 428 {
 429     WX_DECLARE_ANY_VALUE_TYPE(wxAnyValueTypeImplUint)
 430 public:
 431     wxAnyValueTypeImplUint() :
 432         wxAnyValueTypeImplBase<wxAnyBaseUintType>() { }
 433     virtual ~wxAnyValueTypeImplUint() { }
 434
 435     virtual bool ConvertValue(const wxAnyValueBuffer& src,
 436                               wxAnyValueType* dstType,
 437                               wxAnyValueBuffer& dst) const;
 438 };
 439
 440
 441 WX_ANY_DEFINE_SUB_TYPE(signed long, Int)
 442 WX_ANY_DEFINE_SUB_TYPE(signed int, Int)
 443 WX_ANY_DEFINE_SUB_TYPE(signed short, Int)
 444 WX_ANY_DEFINE_SUB_TYPE(signed char, Int)
 445 #ifdef wxLongLong_t
 446 WX_ANY_DEFINE_SUB_TYPE(wxLongLong_t, Int)
 447 #endif
 448
 449 WX_ANY_DEFINE_SUB_TYPE(unsigned long, Uint)
 450 WX_ANY_DEFINE_SUB_TYPE(unsigned int, Uint)
 451 WX_ANY_DEFINE_SUB_TYPE(unsigned short, Uint)
 452 WX_ANY_DEFINE_SUB_TYPE(unsigned char, Uint)
 453 #ifdef wxLongLong_t
 454 WX_ANY_DEFINE_SUB_TYPE(wxULongLong_t, Uint)
 455 #endif
 456
 457
 458 //
 459 // This macro is used in header, but then in source file we must have:
 460 // WX_IMPLEMENT_ANY_VALUE_TYPE(wxAnyValueTypeImpl##TYPENAME)
 461 //
 462 #define _WX_ANY_DEFINE_CONVERTIBLE_TYPE(T, TYPENAME, CONVFUNC, GV) \
 463 class WXDLLIMPEXP_BASE wxAnyValueTypeImpl##TYPENAME : \
 464     public wxAnyValueTypeImplBase<T> \
 465 { \
 466     WX_DECLARE_ANY_VALUE_TYPE(wxAnyValueTypeImpl##TYPENAME) \
 467 public: \
 468     wxAnyValueTypeImpl##TYPENAME() : \
 469         wxAnyValueTypeImplBase<T>() { } \
 470     virtual ~wxAnyValueTypeImpl##TYPENAME() { } \
 471     virtual bool ConvertValue(const wxAnyValueBuffer& src, \
 472                               wxAnyValueType* dstType, \
 473                               wxAnyValueBuffer& dst) const \
 474     { \
 475         GV value = GetValue(src); \
 476         return CONVFUNC(value, dstType, dst); \
 477     } \
 478 }; \
 479 template<> \
 480 class wxAnyValueTypeImpl<T> : public wxAnyValueTypeImpl##TYPENAME \
 481 { \
 482 public: \
 483     wxAnyValueTypeImpl() : wxAnyValueTypeImpl##TYPENAME() { } \
 484     virtual ~wxAnyValueTypeImpl() { } \
 485 };
 486
 487 #define WX_ANY_DEFINE_CONVERTIBLE_TYPE(T, TYPENAME, CONVFUNC, BT) \
 488 _WX_ANY_DEFINE_CONVERTIBLE_TYPE(T, TYPENAME, CONVFUNC, BT) \
 489
 490 #define WX_ANY_DEFINE_CONVERTIBLE_TYPE_BASE(T, TYPENAME, CONVFUNC) \
 491 _WX_ANY_DEFINE_CONVERTIBLE_TYPE(T, TYPENAME, \
 492                                 CONVFUNC, const T&) \
 493
 494 //
 495 // String value type
 496 //
 497
 498 // Convert wxString to destination wxAny value type
 499 extern WXDLLIMPEXP_BASE bool wxAnyConvertString(const wxString& value,
 500                                                 wxAnyValueType* dstType,
 501                                                 wxAnyValueBuffer& dst);
 502
 503 WX_ANY_DEFINE_CONVERTIBLE_TYPE_BASE(wxString, wxString, wxAnyConvertString)
 504 WX_ANY_DEFINE_CONVERTIBLE_TYPE(const char*, ConstCharPtr,
 505                                wxAnyConvertString, wxString)
 506 WX_ANY_DEFINE_CONVERTIBLE_TYPE(const wchar_t*, ConstWchar_tPtr,
 507                                wxAnyConvertString, wxString)
 508
 509 //
 510 // Bool value type
 511 //
 512 template<>
 513 class WXDLLIMPEXP_BASE wxAnyValueTypeImpl<bool> :
 514     public wxAnyValueTypeImplBase<bool>
 515 {
 516     WX_DECLARE_ANY_VALUE_TYPE(wxAnyValueTypeImpl<bool>)
 517 public:
 518     wxAnyValueTypeImpl() :
 519         wxAnyValueTypeImplBase<bool>() { }
 520     virtual ~wxAnyValueTypeImpl() { }
 521
 522     virtual bool ConvertValue(const wxAnyValueBuffer& src,
 523                               wxAnyValueType* dstType,
 524                               wxAnyValueBuffer& dst) const;
 525 };
 526
 527 //
 528 // Floating point value type
 529 //
 530 class WXDLLIMPEXP_BASE wxAnyValueTypeImplDouble :
 531     public wxAnyValueTypeImplBase<double>
 532 {
 533     WX_DECLARE_ANY_VALUE_TYPE(wxAnyValueTypeImplDouble)
 534 public:
 535     wxAnyValueTypeImplDouble() :
 536         wxAnyValueTypeImplBase<double>() { }
 537     virtual ~wxAnyValueTypeImplDouble() { }
 538
 539     virtual bool ConvertValue(const wxAnyValueBuffer& src,
 540                               wxAnyValueType* dstType,
 541                               wxAnyValueBuffer& dst) const;
 542 };
 543
 544 // WX_ANY_DEFINE_SUB_TYPE requires this
 545 typedef double wxAnyBaseDoubleType;
 546
 547 WX_ANY_DEFINE_SUB_TYPE(float, Double)
 548 WX_ANY_DEFINE_SUB_TYPE(double, Double)
 549
 550
 551 //
 552 // Defines a dummy wxAnyValueTypeImpl<> with given export
 553 // declaration. This is needed if a class is used with
 554 // wxAny in both user shared library and application.
 555 //
 556 #define wxDECLARE_ANY_TYPE(CLS, DECL) \
 557 template<> \
 558 class DECL wxAnyValueTypeImpl<CLS> : \
 559     public wxAnyValueTypeImplBase<CLS> \
 560 { \
 561     WX_DECLARE_ANY_VALUE_TYPE(wxAnyValueTypeImpl<CLS>) \
 562 public: \
 563     wxAnyValueTypeImpl() : \
 564         wxAnyValueTypeImplBase<CLS>() { } \
 565     virtual ~wxAnyValueTypeImpl() { } \
 566  \
 567     virtual bool ConvertValue(const wxAnyValueBuffer& src, \
 568                               wxAnyValueType* dstType, \
 569                               wxAnyValueBuffer& dst) const \
 570     { \
 571         wxUnusedVar(src); \
 572         wxUnusedVar(dstType); \
 573         wxUnusedVar(dst); \
 574         return false; \
 575     } \
 576 };
 577
 578
 579 // Make sure some of wx's own types get the right wxAnyValueType export
 580 // (this is needed only for types that are referred to from wxBase.
 581 // currently we may not use any of these types from there, but let's
 582 // use the macro on at least one to make sure it compiles since we can't
 583 // really test it properly in unit tests since a separate DLL would
 584 // be needed).
 585 #if wxUSE_DATETIME
 586     #include "wx/datetime.h"
 587     wxDECLARE_ANY_TYPE(wxDateTime, WXDLLIMPEXP_BASE)
 588 #endif
 589
 590 //#include "wx/object.h"
 591 //wxDECLARE_ANY_TYPE(wxObject*, WXDLLIMPEXP_BASE)
 592
 593 //#include "wx/arrstr.h"
 594 //wxDECLARE_ANY_TYPE(wxArrayString, WXDLLIMPEXP_BASE)
 595
 596
 597 #if wxUSE_VARIANT
 598
 599 class WXDLLIMPEXP_FWD_BASE wxAnyToVariantRegistration;
 600
 601 // Because of header inter-dependencies, cannot include this earlier
 602 #include "wx/variant.h"
 603
 604 //
 605 // wxVariantData* data type implementation. For cases when appropriate
 606 // wxAny<->wxVariant conversion code is missing.
 607 //
 608
 609 class WXDLLIMPEXP_BASE wxAnyValueTypeImplVariantData :
 610     public wxAnyValueTypeImplBase<wxVariantData*>
 611 {
 612     WX_DECLARE_ANY_VALUE_TYPE(wxAnyValueTypeImplVariantData)
 613 public:
 614     wxAnyValueTypeImplVariantData() :
 615         wxAnyValueTypeImplBase<wxVariantData*>() { }
 616     virtual ~wxAnyValueTypeImplVariantData() { }
 617
 618     virtual void DeleteValue(wxAnyValueBuffer& buf) const
 619     {
 620         wxVariantData* data = static_cast<wxVariantData*>(buf.m_ptr);
 621         if ( data )
 622             data->DecRef();
 623     }
 624
 625     virtual void CopyBuffer(const wxAnyValueBuffer& src,
 626                             wxAnyValueBuffer& dst) const
 627     {
 628         wxVariantData* data = static_cast<wxVariantData*>(src.m_ptr);
 629         if ( data )
 630             data->IncRef();
 631         dst.m_ptr = data;
 632     }
 633
 634     static void SetValue(wxVariantData* value,
 635                          wxAnyValueBuffer& buf)
 636     {
 637         value->IncRef();
 638         buf.m_ptr = value;
 639     }
 640
 641     static wxVariantData* GetValue(const wxAnyValueBuffer& buf)
 642     {
 643         return static_cast<wxVariantData*>(buf.m_ptr);
 644     }
 645
 646     virtual bool ConvertValue(const wxAnyValueBuffer& src,
 647                               wxAnyValueType* dstType,
 648                               wxAnyValueBuffer& dst) const
 649     {
 650         wxUnusedVar(src);
 651         wxUnusedVar(dstType);
 652         wxUnusedVar(dst);
 653         return false;
 654     }
 655 };
 656
 657 template<>
 658 class wxAnyValueTypeImpl<wxVariantData*> :
 659     public wxAnyValueTypeImplVariantData
 660 {
 661 public:
 662     wxAnyValueTypeImpl() : wxAnyValueTypeImplVariantData() { }
 663     virtual ~wxAnyValueTypeImpl() { }
 664 };
 665
 666 #endif // wxUSE_VARIANT
 667
 668 #ifdef __VISUALC6__
 669     // Re-enable useless VC6 warnings
 670     #pragma warning (pop)
 671 #endif
 672
 673
 674 /*
 675     Let's define a discrete Null value so we don't have to really
 676     ever check if wxAny.m_type pointer is NULL or not. This is an
 677     optimization, mostly. Implementation of this value type is
 678     "hidden" in the source file.
 679 */
 680 extern WXDLLIMPEXP_DATA_BASE(wxAnyValueType*) wxAnyNullValueType;
 681
 682
 683 //
 684 // We need to implement custom signed/unsigned int equals operators
 685 // for signed/unsigned (eg. wxAny(128UL) == 128L) comparisons to work.
 686 #define WXANY_IMPLEMENT_INT_EQ_OP(TS, TUS) \
 687 bool operator==(TS value) const \
 688 { \
 689     if ( wxAnyValueTypeImpl<TS>::IsSameClass(m_type) ) \
 690         return (value == static_cast<TS> \
 691                 (wxAnyValueTypeImpl<TS>::GetValue(m_buffer))); \
 692     if ( wxAnyValueTypeImpl<TUS>::IsSameClass(m_type) ) \
 693         return (value == static_cast<TS> \
 694                 (wxAnyValueTypeImpl<TUS>::GetValue(m_buffer))); \
 695     return false; \
 696 } \
 697 bool operator==(TUS value) const \
 698 { \
 699     if ( wxAnyValueTypeImpl<TUS>::IsSameClass(m_type) ) \
 700         return (value == static_cast<TUS> \
 701                 (wxAnyValueTypeImpl<TUS>::GetValue(m_buffer))); \
 702     if ( wxAnyValueTypeImpl<TS>::IsSameClass(m_type) ) \
 703         return (value == static_cast<TUS> \
 704                 (wxAnyValueTypeImpl<TS>::GetValue(m_buffer))); \
 705     return false; \
 706 }
 707
 708
 709 #if wxUSE_VARIANT
 710
 711 // Note that the following functions are implemented outside wxAny class
 712 // so that it can reside entirely in header and lack the export declaration.
 713
 714 // Helper function used to associate wxAnyValueType with a wxVariantData.
 715 extern WXDLLIMPEXP_BASE void
 716 wxPreRegisterAnyToVariant(wxAnyToVariantRegistration* reg);
 717
 718 // This function performs main wxAny to wxVariant conversion duties.
 719 extern WXDLLIMPEXP_BASE bool
 720 wxConvertAnyToVariant(const wxAny& any, wxVariant* variant);
 721
 722 #endif // wxUSE_VARIANT
 723
 724
 725 //
 726 // The wxAny class represents a container for any type. A variant's value
 727 // can be changed at run time, possibly to a different type of value.
 728 //
 729 // As standard, wxAny can store value of almost any type, in a fairly
 730 // optimal manner even.
 731 //
 732 class wxAny
 733 {
 734 public:
 735     /**
 736         Default constructor.
 737     */
 738     wxAny()
 739     {
 740         m_type = wxAnyNullValueType;
 741     }
 742
 743     /**
 744         Destructor.
 745     */
 746     ~wxAny()
 747     {
 748         m_type->DeleteValue(m_buffer);
 749     }
 750
 751     //@{
 752     /**
 753         Various constructors.
 754     */
 755     template<typename T>
 756     wxAny(const T& value)
 757     {
 758         m_type = wxAnyValueTypeImpl<T>::sm_instance.get();
 759         wxAnyValueTypeImpl<T>::SetValue(value, m_buffer);
 760     }
 761
 762     // These two constructors are needed to deal with string literals
 763     wxAny(const char* value)
 764     {
 765         m_type = wxAnyValueTypeImpl<const char*>::sm_instance.get();
 766         wxAnyValueTypeImpl<const char*>::SetValue(value, m_buffer);
 767     }
 768     wxAny(const wchar_t* value)
 769     {
 770         m_type = wxAnyValueTypeImpl<const wchar_t*>::sm_instance.get();
 771         wxAnyValueTypeImpl<const wchar_t*>::SetValue(value, m_buffer);
 772     }
 773
 774     wxAny(const wxAny& any)
 775     {
 776         m_type = wxAnyNullValueType;
 777         AssignAny(any);
 778     }
 779
 780 #if wxUSE_VARIANT
 781     wxAny(const wxVariant& variant)
 782     {
 783         m_type = wxAnyNullValueType;
 784         AssignVariant(variant);
 785     }
 786 #endif
 787
 788     //@}
 789
 790     /**
 791         Use this template function for checking if this wxAny holds
 792         a specific C++ data type.
 793
 794         @remarks This template function does not work on some older compilers
 795                 (such as Visual C++ 6.0). For full compiler ccompatibility
 796                 please use wxANY_CHECK_TYPE(any, T) macro instead.
 797
 798         @see wxAnyValueType::CheckType()
 799     */
 800     // FIXME-VC6: remove this hack when VC6 is no longer supported
 801     template <typename T>
 802     bool CheckType(T* = NULL) const
 803     {
 804         return m_type->CheckType<T>();
 805     }
 806
 807     /**
 808         Returns the value type as wxAnyValueType instance.
 809
 810         @remarks You cannot reliably test whether two wxAnys are of
 811                  same value type by simply comparing return values
 812                  of wxAny::GetType(). Instead, use wxAny::HasSameType().
 813
 814         @see HasSameType()
 815     */
 816     const wxAnyValueType* GetType() const
 817     {
 818         return m_type;
 819     }
 820
 821     /**
 822         Returns @true if this and another wxAny have the same
 823         value type.
 824     */
 825     bool HasSameType(const wxAny& other) const
 826     {
 827         return GetType()->IsSameType(other.GetType());
 828     }
 829
 830     /**
 831         Tests if wxAny is null (that is, whether there is no data).
 832     */
 833     bool IsNull() const
 834     {
 835         return (m_type == wxAnyNullValueType);
 836     }
 837
 838     /**
 839         Makes wxAny null (that is, clears it).
 840     */
 841     void MakeNull()
 842     {
 843         m_type->DeleteValue(m_buffer);
 844         m_type = wxAnyNullValueType;
 845     }
 846
 847     //@{
 848     /**
 849         Assignment operators.
 850     */
 851     template<typename T>
 852     wxAny& operator=(const T &value)
 853     {
 854         m_type->DeleteValue(m_buffer);
 855         m_type = wxAnyValueTypeImpl<T>::sm_instance.get();
 856         wxAnyValueTypeImpl<T>::SetValue(value, m_buffer);
 857         return *this;
 858     }
 859
 860     wxAny& operator=(const wxAny &any)
 861     {
 862         if (this != &any)
 863             AssignAny(any);
 864         return *this;
 865     }
 866
 867 #if wxUSE_VARIANT
 868     wxAny& operator=(const wxVariant &variant)
 869     {
 870         AssignVariant(variant);
 871         return *this;
 872     }
 873 #endif
 874
 875     // These two operators are needed to deal with string literals
 876     wxAny& operator=(const char* value)
 877     {
 878         Assign(value);
 879         return *this;
 880     }
 881     wxAny& operator=(const wchar_t* value)
 882     {
 883         Assign(value);
 884         return *this;
 885     }
 886
 887     //@{
 888     /**
 889         Equality operators.
 890     */
 891     bool operator==(const wxString& value) const
 892     {
 893         wxString value2;
 894         if ( !GetAs(&value2) )
 895             return false;
 896         return value == value2;
 897     }
 898
 899     bool operator==(const char* value) const
 900         { return (*this) == wxString(value); }
 901     bool operator==(const wchar_t* value) const
 902         { return (*this) == wxString(value); }
 903
 904     //
 905     // We need to implement custom signed/unsigned int equals operators
 906     // for signed/unsigned (eg. wxAny(128UL) == 128L) comparisons to work.
 907     WXANY_IMPLEMENT_INT_EQ_OP(signed char, unsigned char)
 908     WXANY_IMPLEMENT_INT_EQ_OP(signed short, unsigned short)
 909     WXANY_IMPLEMENT_INT_EQ_OP(signed int, unsigned int)
 910     WXANY_IMPLEMENT_INT_EQ_OP(signed long, unsigned long)
 911 #ifdef wxLongLong_t
 912     WXANY_IMPLEMENT_INT_EQ_OP(wxLongLong_t, wxULongLong_t)
 913 #endif
 914
 915     bool operator==(float value) const
 916     {
 917         if ( !wxAnyValueTypeImpl<float>::IsSameClass(m_type) )
 918             return false;
 919
 920         return value ==
 921             static_cast<float>
 922                 (wxAnyValueTypeImpl<float>::GetValue(m_buffer));
 923     }
 924
 925     bool operator==(double value) const
 926     {
 927         if ( !wxAnyValueTypeImpl<double>::IsSameClass(m_type) )
 928             return false;
 929
 930         return value ==
 931             static_cast<double>
 932                 (wxAnyValueTypeImpl<double>::GetValue(m_buffer));
 933     }
 934
 935     bool operator==(bool value) const
 936     {
 937         if ( !wxAnyValueTypeImpl<bool>::IsSameClass(m_type) )
 938             return false;
 939
 940         return value == (wxAnyValueTypeImpl<bool>::GetValue(m_buffer));
 941     }
 942
 943     //@}
 944
 945     //@{
 946     /**
 947         Inequality operators (implement as template).
 948     */
 949     template<typename T>
 950     bool operator!=(const T& value) const
 951         { return !((*this) == value); }
 952     //@}
 953
 954     /**
 955         This template function converts wxAny into given type. In most cases
 956         no type conversion is performed, so if the type is incorrect an
 957         assertion failure will occur.
 958
 959         @remarks For convenience, conversion is done when T is wxString. This
 960                  is useful when a string literal (which are treated as
 961                  const char* and const wchar_t*) has been assigned to wxAny.
 962
 963                  This template function may not work properly with Visual C++
 964                  6. For full compiler compatibility, please use
 965                  wxANY_AS(any, T) macro instead.
 966     */
 967     // FIXME-VC6: remove this hack when VC6 is no longer supported
 968     template<typename T>
 969     T As(T* = NULL) const
 970     {
 971         if ( !wxAnyValueTypeImpl<T>::IsSameClass(m_type) )
 972         {
 973             wxFAIL_MSG("Incorrect or non-convertible data type");
 974         }
 975
 976         return static_cast<T>(wxAnyValueTypeImpl<T>::GetValue(m_buffer));
 977     }
 978
 979     // Allow easy conversion from 'const char *' etc. to wxString
 980     // FIXME-VC6: remove this hack when VC6 is no longer supported
 981     //template<>
 982     wxString As(wxString*) const
 983     {
 984         wxString value;
 985         if ( !GetAs(&value) )
 986         {
 987             wxFAIL_MSG("Incorrect or non-convertible data type");
 988         }
 989         return value;
 990     }
 991
 992 #if wxUSE_EXTENDED_RTTI
 993     const wxTypeInfo* GetTypeInfo() const
 994     {
 995         return m_type->GetTypeInfo();
 996     }
 997 #endif
 998     /**
 999         Template function that retrieves and converts the value of this
1000         variant to the type that T* value is.
1001
1002         @return Returns @true if conversion was successful.
1003     */
1004     template<typename T>
1005     bool GetAs(T* value) const
1006     {
1007         if ( !wxAnyValueTypeImpl<T>::IsSameClass(m_type) )
1008         {
1009             wxAnyValueType* otherType =
1010                 wxAnyValueTypeImpl<T>::sm_instance.get();
1011             wxAnyValueBuffer temp_buf;
1012
1013             if ( !m_type->ConvertValue(m_buffer, otherType, temp_buf) )
1014                 return false;
1015
1016             *value =
1017                 static_cast<T>(wxAnyValueTypeImpl<T>::GetValue(temp_buf));
1018             otherType->DeleteValue(temp_buf);
1019
1020             return true;
1021         }
1022         *value = static_cast<T>(wxAnyValueTypeImpl<T>::GetValue(m_buffer));
1023         return true;
1024     }
1025
1026 #if wxUSE_VARIANT
1027     // GetAs() wxVariant specialization
1028     bool GetAs(wxVariant* value) const
1029     {
1030         return wxConvertAnyToVariant(*this, value);
1031     }
1032 #endif
1033
1034 private:
1035     // Assignment functions
1036     void AssignAny(const wxAny& any)
1037     {
1038         // Must delete value - CopyBuffer() never does that
1039         m_type->DeleteValue(m_buffer);
1040
1041         wxAnyValueType* newType = any.m_type;
1042
1043         if ( !newType->IsSameType(m_type) )
1044             m_type = newType;
1045
1046         newType->CopyBuffer(any.m_buffer, m_buffer);
1047     }
1048
1049 #if wxUSE_VARIANT
1050     void AssignVariant(const wxVariant& variant)
1051     {
1052         wxVariantData* data = variant.GetData();
1053
1054         if ( data && data->GetAsAny(this) )
1055             return;
1056
1057         m_type->DeleteValue(m_buffer);
1058
1059         if ( variant.IsNull() )
1060         {
1061             // Init as Null
1062             m_type = wxAnyNullValueType;
1063         }
1064         else
1065         {
1066             // If everything else fails, wrap the whole wxVariantData
1067             m_type = wxAnyValueTypeImpl<wxVariantData*>::sm_instance.get();
1068             wxAnyValueTypeImpl<wxVariantData*>::SetValue(data, m_buffer);
1069         }
1070     }
1071 #endif
1072
1073     template<typename T>
1074     void Assign(const T &value)
1075     {
1076         m_type->DeleteValue(m_buffer);
1077         m_type = wxAnyValueTypeImpl<T>::sm_instance.get();
1078         wxAnyValueTypeImpl<T>::SetValue(value, m_buffer);
1079     }
1080
1081     // Data
1082     wxAnyValueBuffer    m_buffer;
1083     wxAnyValueType*     m_type;
1084 };
1085
1086
1087 //
1088 // This method of checking the type is compatible with VC6
1089 #define wxANY_CHECK_TYPE(any, T) \
1090     wxANY_VALUE_TYPE_CHECK_TYPE((any).GetType(), T)
1091
1092
1093 //
1094 // This method of getting the value is compatible with VC6
1095 #define wxANY_AS(any, T) \
1096     (any).As(static_cast<T*>(NULL))
1097
1098
1099 template<typename T>
1100 inline bool wxAnyValueType::CheckType(T* reserved) const
1101 {
1102     wxUnusedVar(reserved);
1103     return wxAnyValueTypeImpl<T>::IsSameClass(this);
1104 }
1105
1106 WX_DECLARE_LIST_WITH_DECL(wxAny, wxAnyList, class WXDLLIMPEXP_BASE);
1107
1108 #endif // wxUSE_ANY
1109
1110 #endif // _WX_ANY_H_