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