clang/test/CXX/temp/temp.fct.spec/temp.deduct/sfinae-1.cpp

   1 // RUN: %clang_cc1 -verify %s
   2 // expected-no-diagnostics
   3
   4 typedef char one_byte;
   5 struct two_bytes { char data[2]; };
   6
   7 template<typename T> one_byte __is_class_check(int T::*);
   8 template<typename T> two_bytes __is_class_check(...);
   9
  10 template<typename T> struct is_class {
  11   static const bool value = sizeof(__is_class_check<T>(0)) == 1;
  12 };
  13
  14 struct X { };
  15
  16 int array0[is_class<X>::value? 1 : -1];
  17 int array1[is_class<int>::value? -1 : 1];
  18 int array2[is_class<char[3]>::value? -1 : 1];
  19
  20 namespace instantiation_order1 {
  21   template<typename T>
  22   struct it_is_a_trap {
  23     typedef typename T::trap type;
  24   };
  25
  26   template<bool, typename T = void>
  27   struct enable_if {
  28     typedef T type;
  29   };
  30
  31   template<typename T>
  32   struct enable_if<false, T> { };
  33
  34   template<typename T>
  35   typename enable_if<sizeof(T) == 17>::type
  36   f(const T&, typename it_is_a_trap<T>::type* = 0);
  37
  38   void f(...);
  39
  40   void test_f() {
  41     f('a');
  42   }
  43 }