]> git.saurik.com Git - wxWidgets.git/blame - include/wx/meta/implicitconversion.h
Implement SelectAll for OSX WebKit.
[wxWidgets.git] / include / wx / meta / implicitconversion.h
CommitLineData
a5247580
VS
1/////////////////////////////////////////////////////////////////////////////
2// Name: wx/meta/implicitconversion.h
3// Purpose: Determine resulting type from implicit conversion
4// Author: Vaclav Slavik
5// Created: 2010-10-22
6// RCS-ID: $Id$
7// Copyright: (c) 2010 Vaclav Slavik
8// Licence: wxWindows licence
9/////////////////////////////////////////////////////////////////////////////
10
11#ifndef _WX_META_IMPLICITCONVERSION_H_
12#define _WX_META_IMPLICITCONVERSION_H_
13
14#include "wx/defs.h"
15#include "wx/meta/if.h"
16
17// C++ hierarchy of data types is:
18//
19// Long double (highest)
20// Double
21// Float
22// Unsigned long int
23// Long int
24// Unsigned int
25// Int (lowest)
26//
27// Types lower in the hierarchy are converted into ones higher up if both are
28// involved e.g. in arithmetic expressions.
29
30namespace wxPrivate
31{
32
25859335
VZ
33// Helper macro to define a constant inside a template class: it's needed
34// because MSVC6 doesn't support initializing static integer members but the
35// usual workaround of using enums instead doesn't work for Borland (at least
36// in template classes).
37#ifdef __VISUALC6__
38 #define wxDEFINE_CLASS_INT_CONST(name, value) enum { name = value }
39#else
40 #define wxDEFINE_CLASS_INT_CONST(name, value) static const int name = value
41#endif
42
a5247580
VS
43template<typename T>
44struct TypeHierarchy
45{
46 // consider unknown types (e.g. objects, pointers) to be of highest
47 // level, always convert to them if they occur
25859335 48 wxDEFINE_CLASS_INT_CONST( level, 9999 );
a5247580
VS
49};
50
51#define WX_TYPE_HIERARCHY_LEVEL(level_num, type) \
52 template<> struct TypeHierarchy<type> \
53 { \
25859335 54 wxDEFINE_CLASS_INT_CONST( level, level_num ); \
530646ca 55 }
a5247580
VS
56
57WX_TYPE_HIERARCHY_LEVEL( 1, char);
58WX_TYPE_HIERARCHY_LEVEL( 2, unsigned char);
59WX_TYPE_HIERARCHY_LEVEL( 3, short);
60WX_TYPE_HIERARCHY_LEVEL( 4, unsigned short);
61WX_TYPE_HIERARCHY_LEVEL( 5, int);
62WX_TYPE_HIERARCHY_LEVEL( 6, unsigned int);
63WX_TYPE_HIERARCHY_LEVEL( 7, long);
64WX_TYPE_HIERARCHY_LEVEL( 8, unsigned long);
65#ifdef wxLongLong_t
66WX_TYPE_HIERARCHY_LEVEL( 9, wxLongLong_t);
67WX_TYPE_HIERARCHY_LEVEL(10, wxULongLong_t);
68#endif
69WX_TYPE_HIERARCHY_LEVEL(11, float);
70WX_TYPE_HIERARCHY_LEVEL(12, double);
71WX_TYPE_HIERARCHY_LEVEL(13, long double);
72
73#if wxWCHAR_T_IS_REAL_TYPE
74 #if SIZEOF_WCHAR_T == SIZEOF_SHORT
75 template<> struct TypeHierarchy<wchar_t> : public TypeHierarchy<short> {};
76 #elif SIZEOF_WCHAR_T == SIZEOF_INT
77 template<> struct TypeHierarchy<wchar_t> : public TypeHierarchy<int> {};
78 #elif SIZEOF_WCHAR_T == SIZEOF_LONG
79 template<> struct TypeHierarchy<wchar_t> : public TypeHierarchy<long> {};
80 #else
81 #error "weird wchar_t size, please update this code"
82 #endif
83#endif
84
85#undef WX_TYPE_HIERARCHY_LEVEL
86
87} // namespace wxPrivate
88
89// Helper to determine resulting type of implicit conversion in
90// an expression with two arithmetic types.
91template<typename T1, typename T2>
92struct wxImplicitConversionType
93{
94 typedef typename wxIf
95 <
96 // if T2 is "higher" type, convert to it
25859335 97 (int)(wxPrivate::TypeHierarchy<T1>::level) < (int)(wxPrivate::TypeHierarchy<T2>::level),
a5247580
VS
98 T2,
99 // otherwise use T1
100 T1
101 >::value
102 value;
103};
104
105
106template<typename T1, typename T2, typename T3>
107struct wxImplicitConversionType3 : public wxImplicitConversionType<
108 T1,
109 typename wxImplicitConversionType<T2,T3>::value>
110{
111};
112
113#endif // _WX_META_IMPLICITCONVERSION_H_