Developer Documentation
GenProg.hh
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47 \*===========================================================================*/
48 
49 
50 //=============================================================================
51 //
52 // Utils for generic/generative programming
53 //
54 //=============================================================================
55 
56 #ifndef OPENMESH_GENPROG_HH
57 #define OPENMESH_GENPROG_HH
58 
59 
60 //== INCLUDES =================================================================
61 
63 
64 
65 //== NAMESPACES ===============================================================
66 
67 namespace OpenMesh {
68 
69 namespace GenProg {
70 #ifndef DOXY_IGNORE_THIS
71 
72 //== IMPLEMENTATION ===========================================================
73 
74 
76 template <bool b> struct Bool2Type { enum { my_bool = b }; };
77 
79 template <int i> struct Int2Type { enum { my_int = i }; };
80 
82 typedef Bool2Type<true> TrueType;
83 
85 typedef Bool2Type<false> FalseType;
86 
87 //-----------------------------------------------------------------------------
89 template <bool Expr> struct AssertCompile;
90 template <> struct AssertCompile<true> {};
91 
92 
93 
94 //--- Template "if" w/ partial specialization ---------------------------------
95 #if OM_PARTIAL_SPECIALIZATION
96 
97 
98 template <bool condition, class Then, class Else>
99 struct IF { typedef Then Result; };
100 
106 template <class Then, class Else>
107 struct IF<false, Then, Else> { typedef Else Result; };
108 
109 
110 
111 
112 
113 //--- Template "if" w/o partial specialization --------------------------------
114 #else
115 
116 
117 struct SelectThen
118 {
119  template <class Then, class Else> struct Select {
120  typedef Then Result;
121  };
122 };
123 
124 struct SelectElse
125 {
126  template <class Then, class Else> struct Select {
127  typedef Else Result;
128  };
129 };
130 
131 template <bool condition> struct ChooseSelector {
132  typedef SelectThen Result;
133 };
134 
135 template <> struct ChooseSelector<false> {
136  typedef SelectElse Result;
137 };
138 
139 
146 template <bool condition, class Then, class Else>
147 class IF
148 {
149  typedef typename ChooseSelector<condition>::Result Selector;
150 public:
151  typedef typename Selector::template Select<Then, Else>::Result Result;
152 };
153 
154 #endif
155 
156 //=============================================================================
157 #endif
158 } // namespace GenProg
159 } // namespace OpenMesh
160 
161 #define assert_compile(EXPR) GenProg::AssertCompile<(EXPR)>();
162 
163 //=============================================================================
164 #endif // OPENMESH_GENPROG_HH defined
165 //=============================================================================