ceph/src/boost/libs/utility/test/result_of_test.cpp

   1 // Boost result_of library
   2
   3 //  Copyright Douglas Gregor 2003-2004. Use, modification and
   4 //  distribution is subject to the Boost Software License, Version
   5 //  1.0. (See accompanying file LICENSE_1_0.txt or copy at
   6 //  http://www.boost.org/LICENSE_1_0.txt)
   7
   8 // Examples:
   9 //   To run the default test:
  10 //   $ cd libs/utility/test && bjam
  11 //   To test decltype on g++ 2.7:
  12 //   $ cd libs/utility/test && bjam cxxflags="-std=c++11 -D BOOST_RESULT_OF_USE_DECLTYPE"
  13
  14 #include <boost/config.hpp>
  15
  16 // For more information, see http://www.boost.org/libs/utility
  17 #include <boost/utility/result_of.hpp>
  18 #include <utility>
  19 #include <boost/static_assert.hpp>
  20 #include <boost/type_traits/is_same.hpp>
  21
  22 struct int_result_type
  23 {
  24   typedef int result_type;
  25   result_type operator()(float);
  26 };
  27
  28 struct int_result_of
  29 {
  30   template<typename F> struct result { typedef int type; };
  31   result<int_result_of(double)>::type operator()(double);
  32   result<const int_result_of(double)>::type operator()(double) const;
  33   result<int_result_of()>::type operator()();
  34   result<volatile int_result_of()>::type operator()() volatile;
  35 };
  36
  37 struct int_result_type_and_float_result_of_and_char_return
  38 {
  39   typedef int result_type;
  40   template<typename F> struct result { typedef float type; };
  41   char operator()(char);
  42 };
  43
  44 template<typename T>
  45 struct int_result_type_template
  46 {
  47   typedef int result_type;
  48   result_type operator()(float);
  49 };
  50
  51 template<typename T>
  52 struct int_result_of_template
  53 {
  54   template<typename F> struct result;
  55   template<typename This, typename That> struct result<This(That)> { typedef int type; };
  56   typename result<int_result_of_template<T>(double)>::type operator()(double);
  57   typename result<const int_result_of_template<T>(double)>::type operator()(double) const;
  58   typename result<int_result_of_template<T>(double)>::type operator()();
  59   typename result<volatile int_result_of_template<T>(double)>::type operator()() volatile;
  60 };
  61
  62 template<typename T>
  63 struct int_result_type_and_float_result_of_and_char_return_template
  64 {
  65   typedef int result_type;
  66   template<typename F> struct result;
  67   template<typename This, typename That> struct result<This(That)> { typedef float type; };
  68   char operator()(char);
  69 };
  70
  71 template<typename T>
  72 struct cv_overload_check {};
  73
  74 struct result_of_member_function_template
  75 {
  76   template<typename F> struct result;
  77
  78   template<typename This, typename That> struct result<This(That)> { typedef That type; };
  79   template<class T> typename result<result_of_member_function_template(T)>::type operator()(T);
  80
  81   template<typename This, typename That> struct result<const This(That)> { typedef cv_overload_check<const That> type; };
  82   template<class T> typename result<const result_of_member_function_template(T)>::type operator()(T) const;
  83
  84   template<typename This, typename That> struct result<volatile This(That)> { typedef cv_overload_check<volatile That> type; };
  85   template<class T> typename result<volatile result_of_member_function_template(T)>::type operator()(T) volatile;
  86
  87   template<typename This, typename That> struct result<const volatile This(That)> { typedef cv_overload_check<const volatile That> type; };
  88   template<class T> typename result<const volatile result_of_member_function_template(T)>::type operator()(T) const volatile;
  89
  90   template<typename This, typename That> struct result<This(That &, That)> { typedef That & type; };
  91   template<class T> typename result<result_of_member_function_template(T &, T)>::type operator()(T &, T);
  92
  93   template<typename This, typename That> struct result<This(That const &, That)> { typedef That const & type; };
  94   template<class T> typename result<result_of_member_function_template(T const &, T)>::type operator()(T const &, T);
  95
  96   template<typename This, typename That> struct result<This(That volatile &, That)> { typedef That volatile & type; };
  97   template<class T> typename result<result_of_member_function_template(T volatile &, T)>::type operator()(T volatile &, T);
  98
  99   template<typename This, typename That> struct result<This(That const volatile &, That)> { typedef That const volatile & type; };
 100   template<class T> typename result<result_of_member_function_template(T const volatile &, T)>::type operator()(T const volatile &, T);
 101 };
 102
 103 struct no_result_type_or_result
 104 {
 105   short operator()(double);
 106   cv_overload_check<const short> operator()(double) const;
 107   cv_overload_check<volatile short> operator()(double) volatile;
 108   cv_overload_check<const volatile short> operator()(double) const volatile;
 109   int operator()();
 110   cv_overload_check<const int> operator()() const;
 111   cv_overload_check<volatile int> operator()() volatile;
 112   cv_overload_check<const volatile int> operator()() const volatile;
 113 #if !defined(BOOST_NO_CXX11_RVALUE_REFERENCES)
 114   short operator()(int&&);
 115   int operator()(int&);
 116   long operator()(int const&);
 117 #endif
 118 };
 119
 120 template<typename T>
 121 struct no_result_type_or_result_template
 122 {
 123   short operator()(double);
 124   cv_overload_check<const short> operator()(double) const;
 125   cv_overload_check<volatile short> operator()(double) volatile;
 126   cv_overload_check<const volatile short> operator()(double) const volatile;
 127   int operator()();
 128   cv_overload_check<const int> operator()() const;
 129   cv_overload_check<volatile int> operator()() volatile;
 130   cv_overload_check<const volatile int> operator()() const volatile;
 131 #if !defined(BOOST_NO_CXX11_RVALUE_REFERENCES)
 132   short operator()(int&&);
 133   int operator()(int&);
 134   long operator()(int const&);
 135 #endif
 136 };
 137
 138 // sfinae_tests are derived from example code from Joel de Guzman,
 139 // which demonstrated the interaction between result_of and SFINAE.
 140 template <typename F, typename Arg>
 141 typename boost::result_of<F(Arg const&)>::type
 142 sfinae_test(F f, Arg const& arg)
 143 {
 144     return f(arg);
 145 }
 146
 147 template <typename F, typename Arg>
 148 typename boost::result_of<F(Arg&)>::type
 149 sfinae_test(F f, Arg& arg)
 150 {
 151     return f(arg);
 152 }
 153
 154 int sfinae_test_f(int& i)
 155 {
 156     return i;
 157 }
 158
 159 struct X {};
 160
 161 int main()
 162 {
 163   using namespace boost;
 164
 165   typedef int (*func_ptr)(float, double);
 166   typedef int (&func_ref)(float, double);
 167   typedef int (*func_ptr_0)();
 168   typedef int (&func_ref_0)();
 169   typedef void (*func_ptr_void)(float, double);
 170   typedef void (&func_ref_void)(float, double);
 171   typedef void (*func_ptr_void_0)();
 172   typedef void (&func_ref_void_0)();
 173   typedef int (X::*mem_func_ptr)(float);
 174   typedef int (X::*mem_func_ptr_c)(float) const;
 175   typedef int (X::*mem_func_ptr_v)(float) volatile;
 176   typedef int (X::*mem_func_ptr_cv)(float) const volatile;
 177   typedef int (X::*mem_func_ptr_0)();
 178
 179   BOOST_STATIC_ASSERT((is_same<result_of<int_result_type(float)>::type, int>::value));
 180   BOOST_STATIC_ASSERT((is_same<result_of<int_result_of(double)>::type, int>::value));
 181   BOOST_STATIC_ASSERT((is_same<result_of<const int_result_of(double)>::type, int>::value));
 182   BOOST_STATIC_ASSERT((is_same<result_of<int_result_type_template<void>(float)>::type, int>::value));
 183   BOOST_STATIC_ASSERT((is_same<result_of<int_result_of_template<void>(double)>::type, int>::value));
 184   BOOST_STATIC_ASSERT((is_same<result_of<const int_result_of_template<void>(double)>::type, int>::value));
 185
 186   BOOST_STATIC_ASSERT((is_same<tr1_result_of<int_result_type(float)>::type, int>::value));
 187   BOOST_STATIC_ASSERT((is_same<tr1_result_of<int_result_of(double)>::type, int>::value));
 188   BOOST_STATIC_ASSERT((is_same<tr1_result_of<const int_result_of(double)>::type, int>::value));
 189   BOOST_STATIC_ASSERT((is_same<tr1_result_of<int_result_type_template<void>(float)>::type, int>::value));
 190   BOOST_STATIC_ASSERT((is_same<tr1_result_of<int_result_of_template<void>(double)>::type, int>::value));
 191   BOOST_STATIC_ASSERT((is_same<tr1_result_of<const int_result_of_template<void>(double)>::type, int>::value));
 192
 193   BOOST_STATIC_ASSERT((is_same<tr1_result_of<int_result_of(void)>::type, void>::value));
 194   BOOST_STATIC_ASSERT((is_same<tr1_result_of<volatile int_result_of(void)>::type, void>::value));
 195   BOOST_STATIC_ASSERT((is_same<tr1_result_of<int_result_of_template<void>(void)>::type, void>::value));
 196   BOOST_STATIC_ASSERT((is_same<tr1_result_of<volatile int_result_of_template<void>(void)>::type, void>::value));
 197
 198   // Prior to decltype, result_of could not deduce the return type
 199   // of nullary function objects unless they exposed a result_type.
 200 #if defined(BOOST_RESULT_OF_USE_DECLTYPE)
 201   BOOST_STATIC_ASSERT((is_same<result_of<int_result_of(void)>::type, int>::value));
 202   BOOST_STATIC_ASSERT((is_same<result_of<volatile int_result_of(void)>::type, int>::value));
 203   BOOST_STATIC_ASSERT((is_same<result_of<int_result_of_template<void>(void)>::type, int>::value));
 204   BOOST_STATIC_ASSERT((is_same<result_of<volatile int_result_of_template<void>(void)>::type, int>::value));
 205 #else
 206   BOOST_STATIC_ASSERT((is_same<result_of<int_result_of(void)>::type, void>::value));
 207   BOOST_STATIC_ASSERT((is_same<result_of<volatile int_result_of(void)>::type, void>::value));
 208   BOOST_STATIC_ASSERT((is_same<result_of<int_result_of_template<void>(void)>::type, void>::value));
 209   BOOST_STATIC_ASSERT((is_same<result_of<volatile int_result_of_template<void>(void)>::type, void>::value));
 210 #endif
 211
 212   // Prior to decltype, result_of ignored a nested result<> if
 213   // result_type was defined. After decltype, result_of deduces the
 214   // actual return type of the function object, ignoring both
 215   // result<> and result_type.
 216 #if defined(BOOST_RESULT_OF_USE_DECLTYPE)
 217   BOOST_STATIC_ASSERT((is_same<result_of<int_result_type_and_float_result_of_and_char_return(char)>::type, char>::value));
 218   BOOST_STATIC_ASSERT((is_same<result_of<int_result_type_and_float_result_of_and_char_return_template<void>(char)>::type, char>::value));
 219 #else
 220   BOOST_STATIC_ASSERT((is_same<result_of<int_result_type_and_float_result_of_and_char_return(char)>::type, int>::value));
 221   BOOST_STATIC_ASSERT((is_same<result_of<int_result_type_and_float_result_of_and_char_return_template<void>(char)>::type, int>::value));
 222 #endif
 223
 224   BOOST_STATIC_ASSERT((is_same<tr1_result_of<int_result_type_and_float_result_of_and_char_return(char)>::type, int>::value));
 225   BOOST_STATIC_ASSERT((is_same<tr1_result_of<int_result_type_and_float_result_of_and_char_return_template<void>(char)>::type, int>::value));
 226
 227   BOOST_STATIC_ASSERT((is_same<result_of<func_ptr(char, float)>::type, int>::value));
 228   BOOST_STATIC_ASSERT((is_same<result_of<func_ref(char, float)>::type, int>::value));
 229   BOOST_STATIC_ASSERT((is_same<result_of<func_ptr_0()>::type, int>::value));
 230   BOOST_STATIC_ASSERT((is_same<result_of<func_ref_0()>::type, int>::value));
 231   BOOST_STATIC_ASSERT((is_same<result_of<func_ptr_void(char, float)>::type, void>::value));
 232   BOOST_STATIC_ASSERT((is_same<result_of<func_ref_void(char, float)>::type, void>::value));
 233   BOOST_STATIC_ASSERT((is_same<result_of<func_ptr_void_0()>::type, void>::value));
 234   BOOST_STATIC_ASSERT((is_same<result_of<func_ref_void_0()>::type, void>::value));
 235   BOOST_STATIC_ASSERT((is_same<result_of<mem_func_ptr(X,char)>::type, int>::value));
 236   BOOST_STATIC_ASSERT((is_same<result_of<mem_func_ptr_c(X,char)>::type, int>::value));
 237   BOOST_STATIC_ASSERT((is_same<result_of<mem_func_ptr_v(X,char)>::type, int>::value));
 238   BOOST_STATIC_ASSERT((is_same<result_of<mem_func_ptr_cv(X,char)>::type, int>::value));
 239   BOOST_STATIC_ASSERT((is_same<result_of<mem_func_ptr_0(X)>::type, int>::value));
 240
 241   BOOST_STATIC_ASSERT((is_same<tr1_result_of<func_ptr(char, float)>::type, int>::value));
 242   BOOST_STATIC_ASSERT((is_same<tr1_result_of<func_ref(char, float)>::type, int>::value));
 243   BOOST_STATIC_ASSERT((is_same<tr1_result_of<func_ptr_0()>::type, int>::value));
 244   BOOST_STATIC_ASSERT((is_same<tr1_result_of<func_ref_0()>::type, int>::value));
 245   BOOST_STATIC_ASSERT((is_same<tr1_result_of<func_ptr_void(char, float)>::type, void>::value));
 246   BOOST_STATIC_ASSERT((is_same<tr1_result_of<func_ref_void(char, float)>::type, void>::value));
 247   BOOST_STATIC_ASSERT((is_same<tr1_result_of<func_ptr_void_0()>::type, void>::value));
 248   BOOST_STATIC_ASSERT((is_same<tr1_result_of<func_ref_void_0()>::type, void>::value));
 249   BOOST_STATIC_ASSERT((is_same<tr1_result_of<mem_func_ptr(X,char)>::type, int>::value));
 250   BOOST_STATIC_ASSERT((is_same<tr1_result_of<mem_func_ptr_c(X,char)>::type, int>::value));
 251   BOOST_STATIC_ASSERT((is_same<tr1_result_of<mem_func_ptr_v(X,char)>::type, int>::value));
 252   BOOST_STATIC_ASSERT((is_same<tr1_result_of<mem_func_ptr_cv(X,char)>::type, int>::value));
 253   BOOST_STATIC_ASSERT((is_same<tr1_result_of<mem_func_ptr_0(X)>::type, int>::value));
 254   BOOST_STATIC_ASSERT((is_same<tr1_result_of<func_ptr(void)>::type, int>::value));
 255   BOOST_STATIC_ASSERT((is_same<tr1_result_of<func_ref(void)>::type, int>::value));
 256
 257   BOOST_STATIC_ASSERT((is_same<result_of<result_of_member_function_template(double)>::type, double>::value));
 258   BOOST_STATIC_ASSERT((is_same<result_of<const result_of_member_function_template(double)>::type, cv_overload_check<const double> >::value));
 259   BOOST_STATIC_ASSERT((is_same<result_of<volatile result_of_member_function_template(double)>::type, cv_overload_check<volatile double> >::value));
 260   BOOST_STATIC_ASSERT((is_same<result_of<const volatile result_of_member_function_template(double)>::type, cv_overload_check<const volatile double> >::value));
 261   BOOST_STATIC_ASSERT((is_same<result_of<result_of_member_function_template(int &, int)>::type, int &>::value));
 262   BOOST_STATIC_ASSERT((is_same<result_of<result_of_member_function_template(int const &, int)>::type, int const &>::value));
 263   BOOST_STATIC_ASSERT((is_same<result_of<result_of_member_function_template(int volatile &, int)>::type, int volatile &>::value));
 264   BOOST_STATIC_ASSERT((is_same<result_of<result_of_member_function_template(int const volatile &, int)>::type, int const volatile &>::value));
 265
 266   BOOST_STATIC_ASSERT((is_same<tr1_result_of<result_of_member_function_template(double)>::type, double>::value));
 267   BOOST_STATIC_ASSERT((is_same<tr1_result_of<const result_of_member_function_template(double)>::type, cv_overload_check<const double> >::value));
 268   BOOST_STATIC_ASSERT((is_same<tr1_result_of<volatile result_of_member_function_template(double)>::type, cv_overload_check<volatile double> >::value));
 269   BOOST_STATIC_ASSERT((is_same<tr1_result_of<const volatile result_of_member_function_template(double)>::type, cv_overload_check<const volatile double> >::value));
 270   BOOST_STATIC_ASSERT((is_same<tr1_result_of<result_of_member_function_template(int &, int)>::type, int &>::value));
 271   BOOST_STATIC_ASSERT((is_same<tr1_result_of<result_of_member_function_template(int const &, int)>::type, int const &>::value));
 272   BOOST_STATIC_ASSERT((is_same<tr1_result_of<result_of_member_function_template(int volatile &, int)>::type, int volatile &>::value));
 273   BOOST_STATIC_ASSERT((is_same<tr1_result_of<result_of_member_function_template(int const volatile &, int)>::type, int const volatile &>::value));
 274
 275   typedef int (*pf_t)(int);
 276   BOOST_STATIC_ASSERT((is_same<result_of<pf_t(int)>::type, int>::value));
 277   BOOST_STATIC_ASSERT((is_same<result_of<pf_t const(int)>::type,int>::value));
 278
 279   BOOST_STATIC_ASSERT((is_same<tr1_result_of<pf_t(int)>::type, int>::value));
 280   BOOST_STATIC_ASSERT((is_same<tr1_result_of<pf_t const(int)>::type,int>::value));
 281
 282 #if defined(BOOST_RESULT_OF_USE_DECLTYPE) || defined(BOOST_RESULT_OF_USE_TR1_WITH_DECLTYPE_FALLBACK)
 283   BOOST_STATIC_ASSERT((is_same<result_of<no_result_type_or_result(double)>::type, short>::value));
 284   BOOST_STATIC_ASSERT((is_same<result_of<const no_result_type_or_result(double)>::type, cv_overload_check<const short> >::value));
 285   BOOST_STATIC_ASSERT((is_same<result_of<volatile no_result_type_or_result(double)>::type, cv_overload_check<volatile short> >::value));
 286   BOOST_STATIC_ASSERT((is_same<result_of<const volatile no_result_type_or_result(double)>::type, cv_overload_check<const volatile short> >::value));
 287   BOOST_STATIC_ASSERT((is_same<result_of<no_result_type_or_result(void)>::type, int>::value));
 288   BOOST_STATIC_ASSERT((is_same<result_of<const no_result_type_or_result(void)>::type, cv_overload_check<const int> >::value));
 289   BOOST_STATIC_ASSERT((is_same<result_of<volatile no_result_type_or_result(void)>::type, cv_overload_check<volatile int> >::value));
 290   BOOST_STATIC_ASSERT((is_same<result_of<const volatile no_result_type_or_result(void)>::type, cv_overload_check<const volatile int> >::value));
 291
 292   BOOST_STATIC_ASSERT((is_same<result_of<no_result_type_or_result_template<void>(double)>::type, short>::value));
 293   BOOST_STATIC_ASSERT((is_same<result_of<const no_result_type_or_result_template<void>(double)>::type, cv_overload_check<const short> >::value));
 294   BOOST_STATIC_ASSERT((is_same<result_of<volatile no_result_type_or_result_template<void>(double)>::type, cv_overload_check<volatile short> >::value));
 295   BOOST_STATIC_ASSERT((is_same<result_of<const volatile no_result_type_or_result_template<void>(double)>::type, cv_overload_check<const volatile short> >::value));
 296   BOOST_STATIC_ASSERT((is_same<result_of<no_result_type_or_result_template<void>(void)>::type, int>::value));
 297   BOOST_STATIC_ASSERT((is_same<result_of<const no_result_type_or_result_template<void>(void)>::type, cv_overload_check<const int> >::value));
 298   BOOST_STATIC_ASSERT((is_same<result_of<volatile no_result_type_or_result_template<void>(void)>::type, cv_overload_check<volatile int> >::value));
 299   BOOST_STATIC_ASSERT((is_same<result_of<const volatile no_result_type_or_result_template<void>(void)>::type, cv_overload_check<const volatile int> >::value));
 300 #if !defined(BOOST_NO_CXX11_RVALUE_REFERENCES)
 301   BOOST_STATIC_ASSERT((is_same<result_of<no_result_type_or_result(int&&)>::type, short>::value));
 302   BOOST_STATIC_ASSERT((is_same<result_of<no_result_type_or_result(int&)>::type, int>::value));
 303   BOOST_STATIC_ASSERT((is_same<result_of<no_result_type_or_result(int const&)>::type, long>::value));
 304   BOOST_STATIC_ASSERT((is_same<result_of<no_result_type_or_result_template<void>(int&&)>::type, short>::value));
 305   BOOST_STATIC_ASSERT((is_same<result_of<no_result_type_or_result_template<void>(int&)>::type, int>::value));
 306   BOOST_STATIC_ASSERT((is_same<result_of<no_result_type_or_result_template<void>(int const&)>::type, long>::value));
 307 #endif
 308 #endif
 309
 310 #if defined(BOOST_RESULT_OF_USE_DECLTYPE) || defined(BOOST_RESULT_OF_USE_TR1_WITH_DECLTYPE_FALLBACK)
 311   int i = 123;
 312   sfinae_test(sfinae_test_f, i);
 313 #endif // defined(BOOST_RESULT_OF_USE_DECLTYPE) || defined(BOOST_RESULT_OF_USE_TR1_WITH_DECLTYPE_FALLBACK)
 314
 315   return 0;
 316 }