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21 
22 
23 
24 #ifndef WW_STATICASSERT_HXX
25 #define WW_STATICASSERT_HXX
26 
27 /*
28  Lifted direct from:
29  Modern C++ Design: Generic Programming and Design Patterns Applied
30  Section 2.1
31  by Andrei Alexandrescu
32 */
33 namespace ww
34 {
35 	template<bool> class compile_time_check
36 	{
37 	public:
compile_time_check(...)38 		compile_time_check(...) {}
39 	};
40 
41 	template<> class compile_time_check<false>
42 	{
43 	};
44 }
45 
46 	/*
47 	Similar to assert, StaticAssert is only in operation when NDEBUG is not
48 	defined. It will test its first argument at compile time and on failure
49 	report the error message of the second argument, which must be a valid c++
50 	classname. i.e. no spaces, punctuation or reserved keywords.
51 	*/
52 #ifndef NDEBUG
53 #	define StaticAssert(test, errormsg)							\
54 	do {														\
55 		struct ERROR_##errormsg {};								\
56 		typedef ww::compile_time_check< (test) != 0 > tmplimpl; \
57 		tmplimpl aTemp = tmplimpl(ERROR_##errormsg());			\
58 		sizeof(aTemp);											\
59 	} while (0)
60 #else
61 #	define StaticAssert(test, errormsg)							\
62 	do {} while (0)
63 #endif
64 
65 #endif
66 
67 /* vim: set noet sw=4 ts=4: */
68