diff options
| -rw-r--r-- | base/template_util.h | 23 | ||||
| -rw-r--r-- | base/template_util_unittest.cc | 10 |
2 files changed, 17 insertions, 16 deletions
diff --git a/base/template_util.h b/base/template_util.h index 0408fc6..e48af91 100644 --- a/base/template_util.h +++ b/base/template_util.h @@ -47,8 +47,6 @@ struct NoType { YesType dummy[2]; }; -#if !defined(OS_WIN) - // This class is an implementation detail for is_convertible, and you // don't need to know how it works to use is_convertible. For those // who care: we declare two different functions, one whose argument is @@ -58,15 +56,17 @@ struct NoType { // had called it with an argument of type From. See Alexandrescu's // _Modern C++ Design_ for more details on this sort of trick. -template <typename From, typename To> struct ConvertHelper { + template <typename To> static YesType Test(To); + + template <typename To> static NoType Test(...); + + template <typename From> static From Create(); }; -#endif // !defined(OS_WIN) - // Used to determine if a type is a struct/union/class. Inspired by Boost's // is_class type_trait implementation. struct IsClassHelper { @@ -79,19 +79,18 @@ struct IsClassHelper { } // namespace internal -#if !defined(OS_WIN) - // Inherits from true_type if From is convertible to To, false_type otherwise. +// +// Note that if the type is convertible, this will be a true_type REGARDLESS +// of whether or not the conversion would emit a warning. template <typename From, typename To> struct is_convertible : integral_constant<bool, - sizeof(internal::ConvertHelper<From, To>::Test( - internal::ConvertHelper<From, To>::Create())) - == sizeof(internal::YesType)> { + sizeof(internal::ConvertHelper::Test<To>( + internal::ConvertHelper::Create<From>())) == + sizeof(internal::YesType)> { }; -#endif // !defined(OS_WIN) - template <typename T> struct is_class : integral_constant<bool, diff --git a/base/template_util_unittest.cc b/base/template_util_unittest.cc index 51d4d33..ea5f0ff 100644 --- a/base/template_util_unittest.cc +++ b/base/template_util_unittest.cc @@ -37,10 +37,8 @@ TEST(TemplateUtilTest, IsNonConstReference) { EXPECT_TRUE(is_non_const_reference<int&>::value); } -#if !defined(OS_WIN) -// TODO(ajwong): Why is is_convertible disabled on windows? TEST(TemplateUtilTest, IsConvertible) { - // Extra parents needed to make EXPECT_*'s parsing happy. Otherwise, + // Extra parens needed to make EXPECT_*'s parsing happy. Otherwise, // it sees the equivalent of // // EXPECT_TRUE( (is_convertible < Child), (Parent > ::value)); @@ -48,8 +46,12 @@ TEST(TemplateUtilTest, IsConvertible) { // Silly C++. EXPECT_TRUE( (is_convertible<Child, Parent>::value) ); EXPECT_FALSE( (is_convertible<Parent, Child>::value) ); + EXPECT_FALSE( (is_convertible<Parent, AStruct>::value) ); + + EXPECT_TRUE( (is_convertible<int, double>::value) ); + EXPECT_TRUE( (is_convertible<int*, void*>::value) ); + EXPECT_FALSE( (is_convertible<void*, int*>::value) ); } -#endif // !defined(OS_WIN) TEST(TemplateUtilTest, IsClass) { EXPECT_TRUE(is_class<AStruct>::value); |