+/*
+ Helpers for defining macros that expand into a single statement.
+
+ The standatd solution is to use "do { ... } while (0)" statement but MSVC
+ generates a C4127 "condition expression is constant" warning for it so we
+ use something which is just complicated enough to not be recognized as a
+ constant but still simple enough to be optimized away.
+
+ Another solution would be to use __pragma() to temporarily disable C4127.
+
+ Notice that wxASSERT_ARG_TYPE in wx/strvargarg.h relies on these macros
+ creating some kind of a loop because it uses "break".
+ */
+#ifdef __WATCOMC__
+ #define wxFOR_ONCE(name) for(int name=0; name<1; name++)
+ #define wxSTATEMENT_MACRO_BEGIN wxFOR_ONCE(wxMAKE_UNIQUE_NAME(wxmacro)) {
+ #define wxSTATEMENT_MACRO_END }
+#else
+ #define wxSTATEMENT_MACRO_BEGIN do {
+ #define wxSTATEMENT_MACRO_END } while ( (void)0, 0 )
+#endif
+
+/*
+ Define __WXFUNCTION__ which is like standard __FUNCTION__ but defined as
+ NULL for the compilers which don't support the latter.
+ */
+#ifndef __WXFUNCTION__
+ /* TODO: add more compilers supporting __FUNCTION__ */
+ #if defined(__DMC__)
+ /*
+ __FUNCTION__ happens to be not defined within class members
+ http://www.digitalmars.com/drn-bin/wwwnews?c%2B%2B.beta/485
+ */
+ #define __WXFUNCTION__ (NULL)
+ #elif defined(__GNUC__) || \
+ (defined(_MSC_VER) && _MSC_VER >= 1300) || \
+ defined(__FUNCTION__)
+ #define __WXFUNCTION__ __FUNCTION__
+ #else
+ /* still define __WXFUNCTION__ to avoid #ifdefs elsewhere */
+ #define __WXFUNCTION__ (NULL)
+ #endif
+#endif /* __WXFUNCTION__ already defined */
+
+
+#if (defined(__STDC_VERSION__) && __STDC_VERSION__ >= 199901L) || \
+ (defined(__cplusplus) && __cplusplus >= 201103L)
+ #define wxHAS_VARIADIC_MACROS
+#elif defined(__GNUC__) && __GNUC__ >= 3
+ #define wxHAS_VARIADIC_MACROS
+#elif defined(_MSC_VER) && _MSC_VER >= 1400
+ #define wxHAS_VARIADIC_MACROS
+#endif
+
+#ifdef wxHAS_VARIADIC_MACROS
+/*
+ wxCALL_FOR_EACH(what, ...) calls the macro from its first argument, what(pos, x),
+ for every remaining argument 'x', with 'pos' being its 1-based index in
+ *reverse* order (with the last argument being numbered 1).
+
+ For example, wxCALL_FOR_EACH(test, a, b, c) expands into this:
+
+ test(3, a) \
+ test(2, b) \
+ test(1, c)
+
+ Up to eight arguments are supported.
+
+ (With thanks to https://groups.google.com/d/topic/comp.std.c/d-6Mj5Lko_s/discussion
+ and http://stackoverflow.com/questions/1872220/is-it-possible-to-iterate-over-arguments-in-variadic-macros)
+*/
+#define wxCALL_FOR_EACH_NARG(...) wxCALL_FOR_EACH_NARG_((__VA_ARGS__, wxCALL_FOR_EACH_RSEQ_N()))
+#define wxCALL_FOR_EACH_NARG_(args) wxCALL_FOR_EACH_ARG_N args
+#define wxCALL_FOR_EACH_ARG_N(_1, _2, _3, _4, _5, _6, _7, _8, N, ...) N
+#define wxCALL_FOR_EACH_RSEQ_N() 8, 7, 6, 5, 4, 3, 2, 1, 0
+
+#define wxCALL_FOR_EACH_1(what, x) what(1, x)
+#define wxCALL_FOR_EACH_2(what, x, ...) what(2, x) wxCALL_FOR_EACH_1(what, __VA_ARGS__)
+#define wxCALL_FOR_EACH_3(what, x, ...) what(3, x) wxCALL_FOR_EACH_2(what, __VA_ARGS__)
+#define wxCALL_FOR_EACH_4(what, x, ...) what(4, x) wxCALL_FOR_EACH_3(what, __VA_ARGS__)
+#define wxCALL_FOR_EACH_5(what, x, ...) what(5, x) wxCALL_FOR_EACH_4(what, __VA_ARGS__)
+#define wxCALL_FOR_EACH_6(what, x, ...) what(6, x) wxCALL_FOR_EACH_5(what, __VA_ARGS__)
+#define wxCALL_FOR_EACH_7(what, x, ...) what(7, x) wxCALL_FOR_EACH_6(what, __VA_ARGS__)
+#define wxCALL_FOR_EACH_8(what, x, ...) what(8, x) wxCALL_FOR_EACH_7(what, __VA_ARGS__)
+
+#define wxCALL_FOR_EACH_(N, args) \
+ wxCONCAT(wxCALL_FOR_EACH_, N) args
+
+#define wxCALL_FOR_EACH(what, ...) \
+ wxCALL_FOR_EACH_(wxCALL_FOR_EACH_NARG(__VA_ARGS__), (what, __VA_ARGS__))
+
+#else
+ #define wxCALL_FOR_EACH Error_wx_CALL_FOR_EACH_requires_variadic_macros_support
+#endif /* wxHAS_VARIADIC_MACROS */
+
projects / wxWidgets.git / blobdiff