FreeFOAM The Cross-Platform CFD Toolkit
StaticAssert.H
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23 
24 Class
25  Foam::StaticAssertionFailed
26 
27 Description
28  Macros and classes to provide static (compile-time) assertions.
29 
30  Ideas from various sources
31  (http://www.ddj.com/cpp/184401547, http://www.boost.org)
32 
33 \*---------------------------------------------------------------------------*/
34 
35 #ifndef StaticAssert_H
36 #define StaticAssert_H
37 
38 namespace Foam
39 {
40 
41 //- Forward declaration of StaticAssertionFailed.
42 // Leave as an incomplete class so that sizeof(..) fails
43 template<bool Truth> class StaticAssertionFailed;
44 
45 /*---------------------------------------------------------------------------*\
46  Class StaticAssertionFailed Declaration
47 \*---------------------------------------------------------------------------*/
48 
49 //- Specialization for successful assertions
50 template<>
52 {};
53 
54 
55 //- Helper class for handling static assertions
56 template<unsigned Test>
58 
59 }
60 
61 // * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
62 
63 // internal use:
64 // ~~~~~~~~~~~~~
65 // paste together strings, even if an argument is itself a macro
66 #define StaticAssertMacro(X,Y) StaticAssertMacro1(X,Y)
67 #define StaticAssertMacro1(X,Y) StaticAssertMacro2(X,Y)
68 #define StaticAssertMacro2(X,Y) X##Y
69 
70 // external use:
71 // ~~~~~~~~~~~~~
76 #define StaticAssert(Test) \
77  typedef ::Foam::StaticAssertionTest \
78  < \
79  sizeof( ::Foam::StaticAssertionFailed< ((Test) ? true : false) > ) \
80  > StaticAssertMacro(StaticAssertionTest, __LINE__)
81 
82 // * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
83 
84 #endif
85 
86 // ************************ vim: set sw=4 sts=4 et: ************************ //