| Index: third_party/cld/base/type_traits.h
|
| ===================================================================
|
| --- third_party/cld/base/type_traits.h (revision 0)
|
| +++ third_party/cld/base/type_traits.h (revision 0)
|
| @@ -0,0 +1,198 @@
|
| +// Copyright (c) 2006-2009 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.
|
| +
|
| +// This code is compiled directly on many platforms, including client
|
| +// platforms like Windows, Mac, and embedded systems. Before making
|
| +// any changes here, make sure that you're not breaking any platforms.
|
| +//
|
| +//
|
| +// Define a small subset of tr1 type traits. The traits we define are:
|
| +// is_integral
|
| +// is_floating_point
|
| +// is_pointer
|
| +// is_reference
|
| +// is_pod
|
| +// has_trivial_constructor
|
| +// has_trivial_copy
|
| +// has_trivial_assign
|
| +// has_trivial_destructor
|
| +// remove_const
|
| +// remove_volatile
|
| +// remove_cv
|
| +// remove_reference
|
| +// remove_pointer
|
| +// is_convertible
|
| +// We can add more type traits as required.
|
| +
|
| +#ifndef BASE_TYPE_TRAITS_H_
|
| +#define BASE_TYPE_TRAITS_H_
|
| +
|
| +#include "third_party/cld/base/template_util.h" // For true_type and false_type
|
| +#include <utility> // For pair
|
| +
|
| +namespace base {
|
| +
|
| +// is_integral is false except for the built-in integer types.
|
| +template <class T> struct is_integral : false_type { };
|
| +template<> struct is_integral<bool> : true_type { };
|
| +template<> struct is_integral<char> : true_type { };
|
| +template<> struct is_integral<unsigned char> : true_type { };
|
| +template<> struct is_integral<signed char> : true_type { };
|
| +#if defined(_MSC_VER)
|
| +// wchar_t is not by default a distinct type from unsigned short in
|
| +// Microsoft C.
|
| +// See http://msdn2.microsoft.com/en-us/library/dh8che7s(VS.80).aspx
|
| +template<> struct is_integral<__wchar_t> : true_type { };
|
| +#else
|
| +template<> struct is_integral<wchar_t> : true_type { };
|
| +#endif
|
| +template<> struct is_integral<short> : true_type { };
|
| +template<> struct is_integral<unsigned short> : true_type { };
|
| +template<> struct is_integral<int> : true_type { };
|
| +template<> struct is_integral<unsigned int> : true_type { };
|
| +template<> struct is_integral<long> : true_type { };
|
| +template<> struct is_integral<unsigned long> : true_type { };
|
| +template<> struct is_integral<long long> : true_type { };
|
| +template<> struct is_integral<unsigned long long> : true_type { };
|
| +
|
| +
|
| +// is_floating_point is false except for the built-in floating-point types.
|
| +template <class T> struct is_floating_point : false_type { };
|
| +template<> struct is_floating_point<float> : true_type { };
|
| +template<> struct is_floating_point<double> : true_type { };
|
| +template<> struct is_floating_point<long double> : true_type { };
|
| +
|
| +
|
| +// is_pointer is false except for pointer types.
|
| +template <class T> struct is_pointer : false_type { };
|
| +template <class T> struct is_pointer<T*> : true_type { };
|
| +
|
| +
|
| +// is_reference is false except for reference types.
|
| +template<typename T> struct is_reference : false_type {};
|
| +template<typename T> struct is_reference<T&> : true_type {};
|
| +
|
| +
|
| +// We can't get is_pod right without compiler help, so fail conservatively.
|
| +// We will assume it's false except for arithmetic types and pointers,
|
| +// and const versions thereof. Note that std::pair is not a POD.
|
| +template <class T> struct is_pod
|
| + : integral_constant<bool, (is_integral<T>::value ||
|
| + is_floating_point<T>::value ||
|
| + is_pointer<T>::value)> { };
|
| +template <class T> struct is_pod<const T> : is_pod<T> { };
|
| +
|
| +
|
| +// We can't get has_trivial_constructor right without compiler help, so
|
| +// fail conservatively. We will assume it's false except for: (1) types
|
| +// for which is_pod is true. (2) std::pair of types with trivial
|
| +// constructors. (3) array of a type with a trivial constructor.
|
| +// (4) const versions thereof.
|
| +template <class T> struct has_trivial_constructor : is_pod<T> { };
|
| +template <class T, class U> struct has_trivial_constructor<std::pair<T, U> >
|
| + : integral_constant<bool,
|
| + (has_trivial_constructor<T>::value &&
|
| + has_trivial_constructor<U>::value)> { };
|
| +template <class A, int N> struct has_trivial_constructor<A[N]>
|
| + : has_trivial_constructor<A> { };
|
| +template <class T> struct has_trivial_constructor<const T>
|
| + : has_trivial_constructor<T> { };
|
| +
|
| +// We can't get has_trivial_copy right without compiler help, so fail
|
| +// conservatively. We will assume it's false except for: (1) types
|
| +// for which is_pod is true. (2) std::pair of types with trivial copy
|
| +// constructors. (3) array of a type with a trivial copy constructor.
|
| +// (4) const versions thereof.
|
| +template <class T> struct has_trivial_copy : is_pod<T> { };
|
| +template <class T, class U> struct has_trivial_copy<std::pair<T, U> >
|
| + : integral_constant<bool,
|
| + (has_trivial_copy<T>::value &&
|
| + has_trivial_copy<U>::value)> { };
|
| +template <class A, int N> struct has_trivial_copy<A[N]>
|
| + : has_trivial_copy<A> { };
|
| +template <class T> struct has_trivial_copy<const T> : has_trivial_copy<T> { };
|
| +
|
| +// We can't get has_trivial_assign right without compiler help, so fail
|
| +// conservatively. We will assume it's false except for: (1) types
|
| +// for which is_pod is true. (2) std::pair of types with trivial copy
|
| +// constructors. (3) array of a type with a trivial assign constructor.
|
| +template <class T> struct has_trivial_assign : is_pod<T> { };
|
| +template <class T, class U> struct has_trivial_assign<std::pair<T, U> >
|
| + : integral_constant<bool,
|
| + (has_trivial_assign<T>::value &&
|
| + has_trivial_assign<U>::value)> { };
|
| +template <class A, int N> struct has_trivial_assign<A[N]>
|
| + : has_trivial_assign<A> { };
|
| +
|
| +// We can't get has_trivial_destructor right without compiler help, so
|
| +// fail conservatively. We will assume it's false except for: (1) types
|
| +// for which is_pod is true. (2) std::pair of types with trivial
|
| +// destructors. (3) array of a type with a trivial destructor.
|
| +// (4) const versions thereof.
|
| +template <class T> struct has_trivial_destructor : is_pod<T> { };
|
| +template <class T, class U> struct has_trivial_destructor<std::pair<T, U> >
|
| + : integral_constant<bool,
|
| + (has_trivial_destructor<T>::value &&
|
| + has_trivial_destructor<U>::value)> { };
|
| +template <class A, int N> struct has_trivial_destructor<A[N]>
|
| + : has_trivial_destructor<A> { };
|
| +template <class T> struct has_trivial_destructor<const T>
|
| + : has_trivial_destructor<T> { };
|
| +
|
| +// Specified by TR1 [4.7.1]
|
| +template<typename T> struct remove_const { typedef T type; };
|
| +template<typename T> struct remove_const<T const> { typedef T type; };
|
| +template<typename T> struct remove_volatile { typedef T type; };
|
| +template<typename T> struct remove_volatile<T volatile> { typedef T type; };
|
| +template<typename T> struct remove_cv {
|
| + typedef typename remove_const<typename remove_volatile<T>::type>::type type;
|
| +};
|
| +
|
| +
|
| +// Specified by TR1 [4.7.2]
|
| +template<typename T> struct remove_reference { typedef T type; };
|
| +template<typename T> struct remove_reference<T&> { typedef T type; };
|
| +
|
| +// Specified by TR1 [4.7.4] Pointer modifications.
|
| +template<typename T> struct remove_pointer { typedef T type; };
|
| +template<typename T> struct remove_pointer<T*> { typedef T type; };
|
| +template<typename T> struct remove_pointer<T* const> { typedef T type; };
|
| +template<typename T> struct remove_pointer<T* volatile> { typedef T type; };
|
| +template<typename T> struct remove_pointer<T* const volatile> {
|
| + typedef T type; };
|
| +
|
| +// Specified by TR1 [4.6] Relationships between types
|
| +#ifndef _MSC_VER
|
| +namespace internal {
|
| +
|
| +// 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();
|
| +};
|
| +} // namespace internal
|
| +
|
| +// 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(small_)> {
|
| +};
|
| +#endif
|
| +
|
| +} // Close namespace base
|
| +
|
| +#endif // BASE_TYPE_TRAITS_H_
|
|
|
| Property changes on: third_party\cld\base\type_traits.h
|
| ___________________________________________________________________
|
| Added: svn:eol-style
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| + LF
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