diff options
Diffstat (limited to 'base/template_util.h')
-rw-r--r-- | base/template_util.h | 47 |
1 files changed, 0 insertions, 47 deletions
diff --git a/base/template_util.h b/base/template_util.h index 27bdb73..2cfe04c 100644 --- a/base/template_util.h +++ b/base/template_util.h @@ -6,8 +6,6 @@ #define BASE_TEMPLATE_UTIL_H_ #pragma once -#include "build/build_config.h" - namespace base { // template definitions from tr1 @@ -27,51 +25,6 @@ typedef integral_constant<bool, false> false_type; template <class T> struct is_pointer : false_type {}; template <class T> struct is_pointer<T*> : true_type {}; -namespace internal { - -// Types small_ and big_ are guaranteed such that sizeof(small_) < -// sizeof(big_) -typedef char small_; - -struct big_ { - small_ 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 -// of type To and one with a variadic argument list. We give them -// return types of different size, so we can use sizeof to trick the -// compiler into telling us which function it would have chosen if we -// 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 { - static small_ Test(To); - static big_ Test(...); - static From Create(); -}; - -#endif // !defined(OS_WIN) - -} // namespace internal - -#if !defined(OS_WIN) - -// Inherits from true_type if From is convertible to To, false_type otherwise. -template <typename From, typename To> -struct is_convertible - : integral_constant<bool, - sizeof(internal::ConvertHelper<From, To>::Test( - internal::ConvertHelper<From, To>::Create())) - == sizeof(internal::small_)> { -}; - -#endif // !defined(OS_WIN) - } // namespace base #endif // BASE_TEMPLATE_UTIL_H_ |