| /* |
| * Copyright (C) 2006, 2007, 2008 Apple Inc. All rights reserved. |
| * Copyright (C) 2009, 2010 Google Inc. All rights reserved. |
| * |
| * This library is free software; you can redistribute it and/or |
| * modify it under the terms of the GNU Library General Public |
| * License as published by the Free Software Foundation; either |
| * version 2 of the License, or (at your option) any later version. |
| * |
| * This library is distributed in the hope that it will be useful, |
| * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| * Library General Public License for more details. |
| * |
| * You should have received a copy of the GNU Library General Public License |
| * along with this library; see the file COPYING.LIB. If not, write to |
| * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, |
| * Boston, MA 02110-1301, USA. |
| * |
| */ |
| |
| #ifndef TypeTraits_h |
| #define TypeTraits_h |
| |
| #include "Platform.h" |
| |
| #if (defined(__GLIBCXX__) && (__GLIBCXX__ >= 20070724) && defined(__GXX_EXPERIMENTAL_CXX0X__)) || (defined(_MSC_VER) && (_MSC_VER >= 1600)) |
| #include <type_traits> |
| #endif |
| |
| namespace WTF { |
| |
| // The following are provided in this file: |
| // |
| // IsInteger<T>::value |
| // IsPod<T>::value, see the definition for a note about its limitations |
| // IsConvertibleToInteger<T>::value |
| // |
| // IsSameType<T, U>::value |
| // |
| // RemovePointer<T>::Type |
| // RemoveConst<T>::Type |
| // RemoveVolatile<T>::Type |
| // RemoveConstVolatile<T>::Type |
| // |
| // COMPILE_ASSERT's in TypeTraits.cpp illustrate their usage and what they do. |
| |
| template<typename T> struct IsInteger { static const bool value = false; }; |
| template<> struct IsInteger<bool> { static const bool value = true; }; |
| template<> struct IsInteger<char> { static const bool value = true; }; |
| template<> struct IsInteger<signed char> { static const bool value = true; }; |
| template<> struct IsInteger<unsigned char> { static const bool value = true; }; |
| template<> struct IsInteger<short> { static const bool value = true; }; |
| template<> struct IsInteger<unsigned short> { static const bool value = true; }; |
| template<> struct IsInteger<int> { static const bool value = true; }; |
| template<> struct IsInteger<unsigned int> { static const bool value = true; }; |
| template<> struct IsInteger<long> { static const bool value = true; }; |
| template<> struct IsInteger<unsigned long> { static const bool value = true; }; |
| template<> struct IsInteger<long long> { static const bool value = true; }; |
| template<> struct IsInteger<unsigned long long> { static const bool value = true; }; |
| #if !COMPILER(MSVC) || defined(_NATIVE_WCHAR_T_DEFINED) |
| template<> struct IsInteger<wchar_t> { static const bool value = true; }; |
| #endif |
| |
| // IsPod is misnamed as it doesn't cover all plain old data (pod) types. |
| // Specifically, it doesn't allow for enums or for structs. |
| template <typename T> struct IsPod { static const bool value = IsInteger<T>::value; }; |
| template <> struct IsPod<float> { static const bool value = true; }; |
| template <> struct IsPod<double> { static const bool value = true; }; |
| template <> struct IsPod<long double> { static const bool value = true; }; |
| template <typename P> struct IsPod<P*> { static const bool value = true; }; |
| |
| // Avoid "possible loss of data" warning when using Microsoft's C++ compiler |
| // by not converting int's to doubles. |
| template<bool performCheck, typename U> class CheckedIsConvertibleToDouble; |
| template<typename U> class CheckedIsConvertibleToDouble<false, U> { |
| public: |
| static const bool value = false; |
| }; |
| |
| template<typename U> class CheckedIsConvertibleToDouble<true, U> { |
| typedef char YesType; |
| struct NoType { |
| char padding[8]; |
| }; |
| |
| static YesType floatCheck(long double); |
| static NoType floatCheck(...); |
| static U& t; |
| public: |
| static const bool value = sizeof(floatCheck(t)) == sizeof(YesType); |
| }; |
| |
| template<typename T> class IsConvertibleToInteger { |
| public: |
| static const bool value = IsInteger<T>::value || CheckedIsConvertibleToDouble<!IsInteger<T>::value, T>::value; |
| }; |
| |
| template <typename T, typename U> struct IsSameType { |
| static const bool value = false; |
| }; |
| |
| template <typename T> struct IsSameType<T, T> { |
| static const bool value = true; |
| }; |
| |
| template <typename T, typename U> class IsSubclass { |
| typedef char YesType; |
| struct NoType { |
| char padding[8]; |
| }; |
| |
| static YesType subclassCheck(U*); |
| static NoType subclassCheck(...); |
| static T* t; |
| public: |
| static const bool value = sizeof(subclassCheck(t)) == sizeof(YesType); |
| }; |
| |
| template <typename T, template<class V> class U> class IsSubclassOfTemplate { |
| typedef char YesType; |
| struct NoType { |
| char padding[8]; |
| }; |
| |
| template<typename W> static YesType subclassCheck(U<W>*); |
| static NoType subclassCheck(...); |
| static T* t; |
| public: |
| static const bool value = sizeof(subclassCheck(t)) == sizeof(YesType); |
| }; |
| |
| template <typename T, template <class V> class OuterTemplate> struct RemoveTemplate { |
| typedef T Type; |
| }; |
| |
| template <typename T, template <class V> class OuterTemplate> struct RemoveTemplate<OuterTemplate<T>, OuterTemplate> { |
| typedef T Type; |
| }; |
| |
| template <typename T> struct RemoveConst { |
| typedef T Type; |
| }; |
| |
| template <typename T> struct RemoveConst<const T> { |
| typedef T Type; |
| }; |
| |
| template <typename T> struct RemoveVolatile { |
| typedef T Type; |
| }; |
| |
| template <typename T> struct RemoveVolatile<volatile T> { |
| typedef T Type; |
| }; |
| |
| template <typename T> struct RemoveConstVolatile { |
| typedef typename RemoveVolatile<typename RemoveConst<T>::Type>::Type Type; |
| }; |
| |
| template <typename T> struct RemovePointer { |
| typedef T Type; |
| }; |
| |
| template <typename T> struct RemovePointer<T*> { |
| typedef T Type; |
| }; |
| |
| #if (defined(__GLIBCXX__) && (__GLIBCXX__ >= 20070724) && defined(__GXX_EXPERIMENTAL_CXX0X__)) || (defined(_MSC_VER) && (_MSC_VER >= 1600)) |
| |
| // GCC's libstdc++ 20070724 and later supports C++ TR1 type_traits in the std namespace. |
| // VC10 (VS2010) and later support C++ TR1 type_traits in the std::tr1 namespace. |
| template<typename T> struct HasTrivialConstructor : public std::tr1::has_trivial_constructor<T> { }; |
| template<typename T> struct HasTrivialDestructor : public std::tr1::has_trivial_destructor<T> { }; |
| |
| #else |
| |
| // This compiler doesn't provide type traits, so we provide basic HasTrivialConstructor |
| // and HasTrivialDestructor definitions. The definitions here include most built-in |
| // scalar types but do not include POD structs and classes. For the intended purposes of |
| // type_traits this results correct but potentially less efficient code. |
| template <typename T, T v> |
| struct IntegralConstant { |
| static const T value = v; |
| typedef T value_type; |
| typedef IntegralConstant<T, v> type; |
| }; |
| |
| typedef IntegralConstant<bool, true> true_type; |
| typedef IntegralConstant<bool, false> false_type; |
| |
| #if defined(_MSC_VER) && (_MSC_VER >= 1400) && !defined(__INTEL_COMPILER) |
| // VC8 (VS2005) and later have built-in compiler support for HasTrivialConstructor / HasTrivialDestructor, |
| // but for some unexplained reason it doesn't work on built-in types. |
| template <typename T> struct HasTrivialConstructor : public IntegralConstant<bool, __has_trivial_constructor(T)>{ }; |
| template <typename T> struct HasTrivialDestructor : public IntegralConstant<bool, __has_trivial_destructor(T)>{ }; |
| #else |
| template <typename T> struct HasTrivialConstructor : public false_type{ }; |
| template <typename T> struct HasTrivialDestructor : public false_type{ }; |
| #endif |
| |
| template <typename T> struct HasTrivialConstructor<T*> : public true_type{ }; |
| template <typename T> struct HasTrivialDestructor<T*> : public true_type{ }; |
| |
| template <> struct HasTrivialConstructor<float> : public true_type{ }; |
| template <> struct HasTrivialConstructor<const float> : public true_type{ }; |
| template <> struct HasTrivialConstructor<volatile float> : public true_type{ }; |
| template <> struct HasTrivialConstructor<const volatile float> : public true_type{ }; |
| |
| template <> struct HasTrivialConstructor<double> : public true_type{ }; |
| template <> struct HasTrivialConstructor<const double> : public true_type{ }; |
| template <> struct HasTrivialConstructor<volatile double> : public true_type{ }; |
| template <> struct HasTrivialConstructor<const volatile double> : public true_type{ }; |
| |
| template <> struct HasTrivialConstructor<long double> : public true_type{ }; |
| template <> struct HasTrivialConstructor<const long double> : public true_type{ }; |
| template <> struct HasTrivialConstructor<volatile long double> : public true_type{ }; |
| template <> struct HasTrivialConstructor<const volatile long double> : public true_type{ }; |
| |
| template <> struct HasTrivialConstructor<unsigned char> : public true_type{ }; |
| template <> struct HasTrivialConstructor<const unsigned char> : public true_type{ }; |
| template <> struct HasTrivialConstructor<volatile unsigned char> : public true_type{ }; |
| template <> struct HasTrivialConstructor<const volatile unsigned char> : public true_type{ }; |
| |
| template <> struct HasTrivialConstructor<unsigned short> : public true_type{ }; |
| template <> struct HasTrivialConstructor<const unsigned short> : public true_type{ }; |
| template <> struct HasTrivialConstructor<volatile unsigned short> : public true_type{ }; |
| template <> struct HasTrivialConstructor<const volatile unsigned short> : public true_type{ }; |
| |
| template <> struct HasTrivialConstructor<unsigned int> : public true_type{ }; |
| template <> struct HasTrivialConstructor<const unsigned int> : public true_type{ }; |
| template <> struct HasTrivialConstructor<volatile unsigned int> : public true_type{ }; |
| template <> struct HasTrivialConstructor<const volatile unsigned int> : public true_type{ }; |
| |
| template <> struct HasTrivialConstructor<unsigned long> : public true_type{ }; |
| template <> struct HasTrivialConstructor<const unsigned long> : public true_type{ }; |
| template <> struct HasTrivialConstructor<volatile unsigned long> : public true_type{ }; |
| template <> struct HasTrivialConstructor<const volatile unsigned long> : public true_type{ }; |
| |
| template <> struct HasTrivialConstructor<unsigned long long> : public true_type{ }; |
| template <> struct HasTrivialConstructor<const unsigned long long> : public true_type{ }; |
| template <> struct HasTrivialConstructor<volatile unsigned long long> : public true_type{ }; |
| template <> struct HasTrivialConstructor<const volatile unsigned long long> : public true_type{ }; |
| |
| template <> struct HasTrivialConstructor<signed char> : public true_type{ }; |
| template <> struct HasTrivialConstructor<const signed char> : public true_type{ }; |
| template <> struct HasTrivialConstructor<volatile signed char> : public true_type{ }; |
| template <> struct HasTrivialConstructor<const volatile signed char> : public true_type{ }; |
| |
| template <> struct HasTrivialConstructor<signed short> : public true_type{ }; |
| template <> struct HasTrivialConstructor<const signed short> : public true_type{ }; |
| template <> struct HasTrivialConstructor<volatile signed short> : public true_type{ }; |
| template <> struct HasTrivialConstructor<const volatile signed short> : public true_type{ }; |
| |
| template <> struct HasTrivialConstructor<signed int> : public true_type{ }; |
| template <> struct HasTrivialConstructor<const signed int> : public true_type{ }; |
| template <> struct HasTrivialConstructor<volatile signed int> : public true_type{ }; |
| template <> struct HasTrivialConstructor<const volatile signed int> : public true_type{ }; |
| |
| template <> struct HasTrivialConstructor<signed long> : public true_type{ }; |
| template <> struct HasTrivialConstructor<const signed long> : public true_type{ }; |
| template <> struct HasTrivialConstructor<volatile signed long> : public true_type{ }; |
| template <> struct HasTrivialConstructor<const volatile signed long> : public true_type{ }; |
| |
| template <> struct HasTrivialConstructor<signed long long> : public true_type{ }; |
| template <> struct HasTrivialConstructor<const signed long long> : public true_type{ }; |
| template <> struct HasTrivialConstructor<volatile signed long long> : public true_type{ }; |
| template <> struct HasTrivialConstructor<const volatile signed long long> : public true_type{ }; |
| |
| template <> struct HasTrivialConstructor<bool> : public true_type{ }; |
| template <> struct HasTrivialConstructor<const bool> : public true_type{ }; |
| template <> struct HasTrivialConstructor<volatile bool> : public true_type{ }; |
| template <> struct HasTrivialConstructor<const volatile bool> : public true_type{ }; |
| |
| template <> struct HasTrivialConstructor<char> : public true_type{ }; |
| template <> struct HasTrivialConstructor<const char> : public true_type{ }; |
| template <> struct HasTrivialConstructor<volatile char> : public true_type{ }; |
| template <> struct HasTrivialConstructor<const volatile char> : public true_type{ }; |
| |
| #if !defined(_MSC_VER) || defined(_NATIVE_WCHAR_T_DEFINED) |
| template <> struct HasTrivialConstructor<wchar_t> : public true_type{ }; |
| template <> struct HasTrivialConstructor<const wchar_t> : public true_type{ }; |
| template <> struct HasTrivialConstructor<volatile wchar_t> : public true_type{ }; |
| template <> struct HasTrivialConstructor<const volatile wchar_t> : public true_type{ }; |
| #endif |
| |
| template <> struct HasTrivialDestructor<float> : public true_type{ }; |
| template <> struct HasTrivialDestructor<const float> : public true_type{ }; |
| template <> struct HasTrivialDestructor<volatile float> : public true_type{ }; |
| template <> struct HasTrivialDestructor<const volatile float> : public true_type{ }; |
| |
| template <> struct HasTrivialDestructor<double> : public true_type{ }; |
| template <> struct HasTrivialDestructor<const double> : public true_type{ }; |
| template <> struct HasTrivialDestructor<volatile double> : public true_type{ }; |
| template <> struct HasTrivialDestructor<const volatile double> : public true_type{ }; |
| |
| template <> struct HasTrivialDestructor<long double> : public true_type{ }; |
| template <> struct HasTrivialDestructor<const long double> : public true_type{ }; |
| template <> struct HasTrivialDestructor<volatile long double> : public true_type{ }; |
| template <> struct HasTrivialDestructor<const volatile long double> : public true_type{ }; |
| |
| template <> struct HasTrivialDestructor<unsigned char> : public true_type{ }; |
| template <> struct HasTrivialDestructor<const unsigned char> : public true_type{ }; |
| template <> struct HasTrivialDestructor<volatile unsigned char> : public true_type{ }; |
| template <> struct HasTrivialDestructor<const volatile unsigned char> : public true_type{ }; |
| |
| template <> struct HasTrivialDestructor<unsigned short> : public true_type{ }; |
| template <> struct HasTrivialDestructor<const unsigned short> : public true_type{ }; |
| template <> struct HasTrivialDestructor<volatile unsigned short> : public true_type{ }; |
| template <> struct HasTrivialDestructor<const volatile unsigned short> : public true_type{ }; |
| |
| template <> struct HasTrivialDestructor<unsigned int> : public true_type{ }; |
| template <> struct HasTrivialDestructor<const unsigned int> : public true_type{ }; |
| template <> struct HasTrivialDestructor<volatile unsigned int> : public true_type{ }; |
| template <> struct HasTrivialDestructor<const volatile unsigned int> : public true_type{ }; |
| |
| template <> struct HasTrivialDestructor<unsigned long> : public true_type{ }; |
| template <> struct HasTrivialDestructor<const unsigned long> : public true_type{ }; |
| template <> struct HasTrivialDestructor<volatile unsigned long> : public true_type{ }; |
| template <> struct HasTrivialDestructor<const volatile unsigned long> : public true_type{ }; |
| |
| template <> struct HasTrivialDestructor<unsigned long long> : public true_type{ }; |
| template <> struct HasTrivialDestructor<const unsigned long long> : public true_type{ }; |
| template <> struct HasTrivialDestructor<volatile unsigned long long> : public true_type{ }; |
| template <> struct HasTrivialDestructor<const volatile unsigned long long> : public true_type{ }; |
| |
| template <> struct HasTrivialDestructor<signed char> : public true_type{ }; |
| template <> struct HasTrivialDestructor<const signed char> : public true_type{ }; |
| template <> struct HasTrivialDestructor<volatile signed char> : public true_type{ }; |
| template <> struct HasTrivialDestructor<const volatile signed char> : public true_type{ }; |
| |
| template <> struct HasTrivialDestructor<signed short> : public true_type{ }; |
| template <> struct HasTrivialDestructor<const signed short> : public true_type{ }; |
| template <> struct HasTrivialDestructor<volatile signed short> : public true_type{ }; |
| template <> struct HasTrivialDestructor<const volatile signed short> : public true_type{ }; |
| |
| template <> struct HasTrivialDestructor<signed int> : public true_type{ }; |
| template <> struct HasTrivialDestructor<const signed int> : public true_type{ }; |
| template <> struct HasTrivialDestructor<volatile signed int> : public true_type{ }; |
| template <> struct HasTrivialDestructor<const volatile signed int> : public true_type{ }; |
| |
| template <> struct HasTrivialDestructor<signed long> : public true_type{ }; |
| template <> struct HasTrivialDestructor<const signed long> : public true_type{ }; |
| template <> struct HasTrivialDestructor<volatile signed long> : public true_type{ }; |
| template <> struct HasTrivialDestructor<const volatile signed long> : public true_type{ }; |
| |
| template <> struct HasTrivialDestructor<signed long long> : public true_type{ }; |
| template <> struct HasTrivialDestructor<const signed long long> : public true_type{ }; |
| template <> struct HasTrivialDestructor<volatile signed long long> : public true_type{ }; |
| template <> struct HasTrivialDestructor<const volatile signed long long> : public true_type{ }; |
| |
| template <> struct HasTrivialDestructor<bool> : public true_type{ }; |
| template <> struct HasTrivialDestructor<const bool> : public true_type{ }; |
| template <> struct HasTrivialDestructor<volatile bool> : public true_type{ }; |
| template <> struct HasTrivialDestructor<const volatile bool> : public true_type{ }; |
| |
| template <> struct HasTrivialDestructor<char> : public true_type{ }; |
| template <> struct HasTrivialDestructor<const char> : public true_type{ }; |
| template <> struct HasTrivialDestructor<volatile char> : public true_type{ }; |
| template <> struct HasTrivialDestructor<const volatile char> : public true_type{ }; |
| |
| #if !defined(_MSC_VER) || defined(_NATIVE_WCHAR_T_DEFINED) |
| template <> struct HasTrivialDestructor<wchar_t> : public true_type{ }; |
| template <> struct HasTrivialDestructor<const wchar_t> : public true_type{ }; |
| template <> struct HasTrivialDestructor<volatile wchar_t> : public true_type{ }; |
| template <> struct HasTrivialDestructor<const volatile wchar_t> : public true_type{ }; |
| #endif |
| |
| #endif // __GLIBCXX__, etc. |
| |
| } // namespace WTF |
| |
| #endif // TypeTraits_h |