197 lines
		
	
	
		
			7.5 KiB
		
	
	
	
		
			C++
		
	
	
	
	
	
			
		
		
	
	
			197 lines
		
	
	
		
			7.5 KiB
		
	
	
	
		
			C++
		
	
	
	
	
	
| /*
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|  *  Name:        wx/cpp.h
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|  *  Purpose:     Various preprocessor helpers
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|  *  Author:      Vadim Zeitlin
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|  *  Created:     2006-09-30
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|  *  Copyright:   (c) 2006 Vadim Zeitlin <vadim@wxwindows.org>
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|  *  Licence:     wxWindows licence
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|  */
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| 
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| /* THIS IS A C FILE, DON'T USE C++ FEATURES (IN PARTICULAR COMMENTS) IN IT */
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| 
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| #ifndef _WX_CPP_H_
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| #define _WX_CPP_H_
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| 
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| #include "wx/compiler.h"    /* wxCHECK_XXX_VERSION() macros */
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| 
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| /* wxCONCAT works like preprocessor ## operator but also works with macros */
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| #define wxCONCAT_HELPER(text, line) text ## line
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| 
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| #define wxCONCAT(x1, x2) \
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|     wxCONCAT_HELPER(x1, x2)
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| #define wxCONCAT3(x1, x2, x3) \
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|     wxCONCAT(wxCONCAT(x1, x2), x3)
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| #define wxCONCAT4(x1, x2, x3, x4) \
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|     wxCONCAT(wxCONCAT3(x1, x2, x3), x4)
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| #define wxCONCAT5(x1, x2, x3, x4, x5) \
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|     wxCONCAT(wxCONCAT4(x1, x2, x3, x4), x5)
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| #define wxCONCAT6(x1, x2, x3, x4, x5, x6) \
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|     wxCONCAT(wxCONCAT5(x1, x2, x3, x4, x5), x6)
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| #define wxCONCAT7(x1, x2, x3, x4, x5, x6, x7) \
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|     wxCONCAT(wxCONCAT6(x1, x2, x3, x4, x5, x6), x7)
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| #define wxCONCAT8(x1, x2, x3, x4, x5, x6, x7, x8) \
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|     wxCONCAT(wxCONCAT7(x1, x2, x3, x4, x5, x6, x7), x8)
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| #define wxCONCAT9(x1, x2, x3, x4, x5, x6, x7, x8, x9) \
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|     wxCONCAT(wxCONCAT8(x1, x2, x3, x4, x5, x6, x7, x8), x9)
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| 
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| /* wxSTRINGIZE works as the preprocessor # operator but also works with macros */
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| #define wxSTRINGIZE_HELPER(x)       #x
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| #define wxSTRINGIZE(x)              wxSTRINGIZE_HELPER(x)
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| 
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| /* a Unicode-friendly version of wxSTRINGIZE_T */
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| #define wxSTRINGIZE_T(x)            wxAPPLY_T(wxSTRINGIZE(x))
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| 
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| /*
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|     Special workarounds for compilers with broken "##" operator. For all the
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|     other ones we can just use it directly.
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|  */
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| #ifdef wxCOMPILER_BROKEN_CONCAT_OPER
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|     #define wxPREPEND_L(x)      L ## x
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|     #define wxAPPEND_i64(x)     x ## i64
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|     #define wxAPPEND_ui64(x)    x ## ui64
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| #endif /* wxCOMPILER_BROKEN_CONCAT_OPER */
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| 
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| /*
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|    Helper macros for wxMAKE_UNIQUE_NAME: normally this works by appending the
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|    current line number to the given identifier to reduce the probability of the
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|    conflict (it may still happen if this is used in the headers, hence you
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|    should avoid doing it or provide unique prefixes then) but we have to do it
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|    differently for VC++
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|   */
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| #if defined(__VISUALC__)
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|     /*
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|        __LINE__ handling is completely broken in VC++ when using "Edit and
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|        Continue" (/ZI option) and results in preprocessor errors if we use it
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|        inside the macros. Luckily VC7 has another standard macro which can be
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|        used like this and is even better than __LINE__ because it is globally
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|        unique.
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|      */
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| #   define wxCONCAT_LINE(text)         wxCONCAT(text, __COUNTER__)
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| #else /* normal compilers */
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| #   define wxCONCAT_LINE(text)         wxCONCAT(text, __LINE__)
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| #endif
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| 
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| /* Create a "unique" name with the given prefix */
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| #define wxMAKE_UNIQUE_NAME(text)    wxCONCAT_LINE(text)
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| 
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| /*
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|    This macro can be passed as argument to another macro when you don't have
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|    anything to pass in fact.
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|  */
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| #define wxEMPTY_PARAMETER_VALUE /* Fake macro parameter value */
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| 
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| /*
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|     Helpers for defining macros that expand into a single statement.
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| 
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|     The standard solution is to use "do { ... } while (0)" statement but MSVC
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|     generates a C4127 "condition expression is constant" warning for it so we
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|     use something which is just complicated enough to not be recognized as a
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|     constant but still simple enough to be optimized away.
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| 
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|     Another solution would be to use __pragma() to temporarily disable C4127.
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| 
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|     Notice that wxASSERT_ARG_TYPE in wx/strvargarg.h relies on these macros
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|     creating some kind of a loop because it uses "break".
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|  */
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| #define wxSTATEMENT_MACRO_BEGIN  do {
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| #define wxSTATEMENT_MACRO_END } while ( (void)0, 0 )
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| 
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| /*
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|     Define __WXFUNCTION__ which is like standard __FUNCTION__ but defined as
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|     NULL for the compilers which don't support the latter.
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|  */
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| #ifndef __WXFUNCTION__
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|     #if defined(__GNUC__) || \
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|           defined(__VISUALC__) || \
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|           defined(__FUNCTION__)
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|         #define __WXFUNCTION__ __FUNCTION__
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|     #else
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|         /* still define __WXFUNCTION__ to avoid #ifdefs elsewhere */
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|         #define __WXFUNCTION__ (NULL)
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|     #endif
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| #endif /* __WXFUNCTION__ already defined */
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| 
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| 
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| /* Auto-detect variadic macros support unless explicitly disabled. */
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| #if !defined(HAVE_VARIADIC_MACROS) && !defined(wxNO_VARIADIC_MACROS)
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|     /* Any C99 or C++11 compiler should have them. */
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|     #if (defined(__STDC_VERSION__) && __STDC_VERSION__ >= 199901L) || \
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|         (defined(__cplusplus) && __cplusplus >= 201103L)
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|         #define HAVE_VARIADIC_MACROS 1
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|     #elif defined(__GNUC__)
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|         #define HAVE_VARIADIC_MACROS 1
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|     #elif wxCHECK_VISUALC_VERSION(8)
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|         #define HAVE_VARIADIC_MACROS 1
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|     #endif
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| #endif /* !HAVE_VARIADIC_MACROS */
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| 
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| 
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| 
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| #ifdef HAVE_VARIADIC_MACROS
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| 
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| /*
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|    This is a hack to make it possible to use variadic macros with g++ 3.x even
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|    when using -pedantic[-errors] option: without this, it would complain that
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| 
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|        "anonymous variadic macros were introduced in C99"
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| 
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|    and the option disabling this warning (-Wno-variadic-macros) is only
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|    available in gcc 4.0 and later, so until then this hack is the only thing we
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|    can do.
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|  */
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| #if defined(__GNUC__) && __GNUC__ == 3
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|     #pragma GCC system_header
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| #endif /* gcc-3.x */
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| 
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| /*
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|    wxCALL_FOR_EACH(what, ...) calls the macro from its first argument, what(pos, x),
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|    for every remaining argument 'x', with 'pos' being its 1-based index in
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|    *reverse* order (with the last argument being numbered 1).
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| 
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|    For example, wxCALL_FOR_EACH(test, a, b, c) expands into this:
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| 
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|        test(3, a) \
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|        test(2, b) \
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|        test(1, c)
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| 
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|    Up to eight arguments are supported.
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| 
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|    (With thanks to https://groups.google.com/d/topic/comp.std.c/d-6Mj5Lko_s/discussion
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|    and https://stackoverflow.com/questions/1872220/is-it-possible-to-iterate-over-arguments-in-variadic-macros)
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| */
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| #define wxCALL_FOR_EACH_NARG(...)   wxCALL_FOR_EACH_NARG_((__VA_ARGS__, wxCALL_FOR_EACH_RSEQ_N()))
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| #define wxCALL_FOR_EACH_NARG_(args) wxCALL_FOR_EACH_ARG_N args
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| #define wxCALL_FOR_EACH_ARG_N(_1, _2, _3, _4, _5, _6, _7, _8, N, ...) N
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| #define wxCALL_FOR_EACH_RSEQ_N() 8, 7, 6, 5, 4, 3, 2, 1, 0
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| 
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| #define wxCALL_FOR_EACH_1_(args)   wxCALL_FOR_EACH_1 args
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| #define wxCALL_FOR_EACH_2_(args)   wxCALL_FOR_EACH_2 args
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| #define wxCALL_FOR_EACH_3_(args)   wxCALL_FOR_EACH_3 args
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| #define wxCALL_FOR_EACH_4_(args)   wxCALL_FOR_EACH_4 args
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| #define wxCALL_FOR_EACH_5_(args)   wxCALL_FOR_EACH_5 args
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| #define wxCALL_FOR_EACH_6_(args)   wxCALL_FOR_EACH_6 args
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| #define wxCALL_FOR_EACH_7_(args)   wxCALL_FOR_EACH_7 args
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| #define wxCALL_FOR_EACH_8_(args)   wxCALL_FOR_EACH_8 args
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| 
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| #define wxCALL_FOR_EACH_1(what, x)        what(1, x)
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| #define wxCALL_FOR_EACH_2(what, x, ...)   what(2, x)  wxCALL_FOR_EACH_1_((what, __VA_ARGS__))
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| #define wxCALL_FOR_EACH_3(what, x, ...)   what(3, x)  wxCALL_FOR_EACH_2_((what, __VA_ARGS__))
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| #define wxCALL_FOR_EACH_4(what, x, ...)   what(4, x)  wxCALL_FOR_EACH_3_((what, __VA_ARGS__))
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| #define wxCALL_FOR_EACH_5(what, x, ...)   what(5, x)  wxCALL_FOR_EACH_4_((what, __VA_ARGS__))
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| #define wxCALL_FOR_EACH_6(what, x, ...)   what(6, x)  wxCALL_FOR_EACH_5_((what, __VA_ARGS__))
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| #define wxCALL_FOR_EACH_7(what, x, ...)   what(7, x)  wxCALL_FOR_EACH_6_((what, __VA_ARGS__))
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| #define wxCALL_FOR_EACH_8(what, x, ...)   what(8, x)  wxCALL_FOR_EACH_7_((what, __VA_ARGS__))
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| 
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| #define wxCALL_FOR_EACH_(N, args) \
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|     wxCONCAT(wxCALL_FOR_EACH_, N) args
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| 
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| #define wxCALL_FOR_EACH(what, ...) \
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|     wxCALL_FOR_EACH_(wxCALL_FOR_EACH_NARG(__VA_ARGS__), (what, __VA_ARGS__))
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| 
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| #else
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|     #define wxCALL_FOR_EACH  Error_wx_CALL_FOR_EACH_requires_variadic_macros_support
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| #endif /* HAVE_VARIADIC_MACROS */
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| 
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| #endif /* _WX_CPP_H_ */
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| 
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