Replace template_util.h stuff with C++11 <type_traits>

base/template_util.h

 // Copyright (c) 2011 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef BASE_TEMPLATE_UTIL_H_
 #define BASE_TEMPLATE_UTIL_H_
 
-#include <stddef.h>
+#include <type_traits>
 
 #include "build/build_config.h"
 
 namespace base {
 
-// template definitions from tr1
-
-template<class T, T v>
-struct integral_constant {
-  static const T value = v;
-  typedef T value_type;
-  typedef integral_constant<T, v> type;
-};
-
-template <class T, T v> const T integral_constant<T, v>::value;
-
-typedef integral_constant<bool, true> true_type;
-typedef integral_constant<bool, false> false_type;
-
-template <class T> struct is_pointer : false_type {};
-template <class T> struct is_pointer<T*> : true_type {};
-
-// Member function pointer detection. This is built-in to C++ 11's stdlib, and
-// we can remove this when we switch to it.
-template<typename T>
-struct is_member_function_pointer : false_type {};
-
-template <typename R, typename Z, typename... A>
-struct is_member_function_pointer<R(Z::*)(A...)> : true_type {};
-template <typename R, typename Z, typename... A>
-struct is_member_function_pointer<R(Z::*)(A...) const> : true_type {};
-
-
-template <class T, class U> struct is_same : public false_type {};
-template <class T> struct is_same<T,T> : true_type {};
-
-template<class> struct is_array : public false_type {};
-template<class T, size_t n> struct is_array<T[n]> : public true_type {};
-template<class T> struct is_array<T[]> : public true_type {};
-
-template <class T> struct is_non_const_reference : false_type {};
-template <class T> struct is_non_const_reference<T&> : true_type {};
-template <class T> struct is_non_const_reference<const T&> : false_type {};
-
-template <class T> struct is_const : false_type {};
-template <class T> struct is_const<const T> : true_type {};
-
-template <class T> struct is_void : false_type {};
-template <> struct is_void<void> : true_type {};
-
-namespace internal {
-
-// Types YesType and NoType are guaranteed such that sizeof(YesType) <
-// sizeof(NoType).
-typedef char YesType;
-
-struct NoType {
-  YesType dummy[2];
-};
-
-// 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.
-
-struct ConvertHelper {
-  template <typename To>
-  static YesType Test(To);
-
-  template <typename To>
-  static NoType Test(...);
-
-  template <typename From>
-  static From& Create();
-};
-
-// Used to determine if a type is a struct/union/class. Inspired by Boost's
-// is_class type_trait implementation.
-struct IsClassHelper {
-  template <typename C>
-  static YesType Test(void(C::*)(void));
-
-  template <typename C>
-  static NoType Test(...);
-};
-
-}  // namespace internal
-
-// 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::Test<To>(
-                                   internal::ConvertHelper::Create<From>())) ==
-                        sizeof(internal::YesType)> {
-};
-
-template <typename T>
-struct is_class
-    : integral_constant<bool,
-                        sizeof(internal::IsClassHelper::Test<T>(0)) ==
-                            sizeof(internal::YesType)> {
-};
+template <class T> struct is_non_const_reference : std::false_type {};
+template <class T> struct is_non_const_reference<T&> : std::true_type {};
+template <class T> struct is_non_const_reference<const T&> : std::false_type {};
 
 }  // namespace base
 
 #endif  // BASE_TEMPLATE_UTIL_H_