[libcxx] Add std::any
Summary:
This patch adds std::any by moving/adapting <experimental/any>.
This patch also implements the std::any parts of p0032r3 (http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2016/p0032r3.pdf)
and LWG 2509 (http://cplusplus.github.io/LWG/lwg-defects.html#2509).
I plan to push it in a day or two if there are no comments.
Reviewers: mclow.lists, EricWF
Subscribers: cfe-commits
Differential Revision: https://reviews.llvm.org/D22733
git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@278310 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/include/any b/include/any
new file mode 100644
index 0000000..d6ae063
--- /dev/null
+++ b/include/any
@@ -0,0 +1,658 @@
+// -*- C++ -*-
+//===------------------------------ any -----------------------------------===//
+//
+// The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP_ANY
+#define _LIBCPP_ANY
+
+/*
+ any synopsis
+
+namespace std {
+
+ class bad_any_cast : public bad_cast
+ {
+ public:
+ virtual const char* what() const noexcept;
+ };
+
+ class any
+ {
+ public:
+
+ // 6.3.1 any construct/destruct
+ any() noexcept;
+
+ any(const any& other);
+ any(any&& other) noexcept;
+
+ template <class ValueType>
+ any(ValueType&& value);
+
+ ~any();
+
+ // 6.3.2 any assignments
+ any& operator=(const any& rhs);
+ any& operator=(any&& rhs) noexcept;
+
+ template <class ValueType>
+ any& operator=(ValueType&& rhs);
+
+ // 6.3.3 any modifiers
+ void reset() noexcept;
+ void swap(any& rhs) noexcept;
+
+ // 6.3.4 any observers
+ bool has_value() const noexcept;
+ const type_info& type() const noexcept;
+ };
+
+ // 6.4 Non-member functions
+ void swap(any& x, any& y) noexcept;
+
+ template <class T, class ...Args>
+ any make_any(Args&& ...args);
+ template <class T, class U, class ...Args>
+ any make_any(initializer_list<U>, Args&& ...args);
+
+ template<class ValueType>
+ ValueType any_cast(const any& operand);
+ template<class ValueType>
+ ValueType any_cast(any& operand);
+ template<class ValueType>
+ ValueType any_cast(any&& operand);
+
+ template<class ValueType>
+ const ValueType* any_cast(const any* operand) noexcept;
+ template<class ValueType>
+ ValueType* any_cast(any* operand) noexcept;
+
+} // namespace fundamentals_v1
+} // namespace experimental
+} // namespace std
+
+*/
+
+#include <experimental/__config>
+#include <memory>
+#include <new>
+#include <typeinfo>
+#include <type_traits>
+#include <cstdlib>
+#include <cassert>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+#pragma GCC system_header
+#endif
+
+namespace std {
+class _LIBCPP_EXCEPTION_ABI bad_any_cast : public bad_cast
+{
+public:
+ virtual const char* what() const _NOEXCEPT;
+};
+} // namespace std
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER > 14
+
+// Forward declarations
+class _LIBCPP_TYPE_VIS_ONLY any;
+
+template <class _ValueType>
+_LIBCPP_INLINE_VISIBILITY
+add_pointer_t<add_const_t<_ValueType>>
+any_cast(any const *) _NOEXCEPT;
+
+template <class _ValueType>
+_LIBCPP_INLINE_VISIBILITY
+add_pointer_t<_ValueType> any_cast(any *) _NOEXCEPT;
+
+namespace __any_imp
+{
+ using _Buffer = aligned_storage_t<3*sizeof(void*), alignment_of<void*>::value>;
+
+ template <class _Tp>
+ using _IsSmallObject = integral_constant<bool
+ , sizeof(_Tp) <= sizeof(_Buffer)
+ && alignment_of<_Buffer>::value
+ % alignment_of<_Tp>::value == 0
+ && is_nothrow_move_constructible<_Tp>::value
+ >;
+
+ enum class _Action {
+ _Destroy,
+ _Copy,
+ _Move,
+ _Get,
+ _TypeInfo
+ };
+
+ template <class _Tp> struct _SmallHandler;
+ template <class _Tp> struct _LargeHandler;
+
+ template <class _Tp>
+ struct _LIBCPP_TYPE_VIS_ONLY __unique_typeinfo { static constexpr int __id = 0; };
+ template <class _Tp> constexpr int __unique_typeinfo<_Tp>::__id;
+
+ template <class _Tp>
+ inline _LIBCPP_INLINE_VISIBILITY
+ constexpr const void* __get_fallback_typeid() {
+ return &__unique_typeinfo<decay_t<_Tp>>::__id;
+ }
+
+ template <class _Tp>
+ inline _LIBCPP_INLINE_VISIBILITY
+ bool __compare_typeid(type_info const* __id, const void* __fallback_id)
+ {
+#if !defined(_LIBCPP_NO_RTTI)
+ if (__id && *__id == typeid(_Tp))
+ return true;
+#endif
+ if (!__id && __fallback_id == __any_imp::__get_fallback_typeid<_Tp>())
+ return true;
+ return false;
+ }
+
+ template <class _Tp>
+ using _Handler = conditional_t<
+ _IsSmallObject<_Tp>::value, _SmallHandler<_Tp>, _LargeHandler<_Tp>>;
+
+} // namespace __any_imp
+
+class _LIBCPP_TYPE_VIS_ONLY any
+{
+public:
+ // construct/destruct
+ _LIBCPP_INLINE_VISIBILITY
+ constexpr any() _NOEXCEPT : __h(nullptr) {}
+
+ _LIBCPP_INLINE_VISIBILITY
+ any(any const & __other) : __h(nullptr)
+ {
+ if (__other.__h) __other.__call(_Action::_Copy, this);
+ }
+
+ _LIBCPP_INLINE_VISIBILITY
+ any(any && __other) _NOEXCEPT : __h(nullptr)
+ {
+ if (__other.__h) __other.__call(_Action::_Move, this);
+ }
+
+ template <
+ class _ValueType
+ , class = enable_if_t<
+ !is_same<decay_t<_ValueType>, any>::value &&
+ !__is_inplace_type<_ValueType>::value &&
+ is_copy_constructible<_ValueType>::value>
+ >
+ _LIBCPP_INLINE_VISIBILITY
+ any(_ValueType && __value);
+
+ template <class _Tp, class ..._Args,
+ class = enable_if_t<
+ is_constructible<_Tp, _Args...>::value &&
+ is_copy_constructible<_Tp>::value
+ >
+ >
+ _LIBCPP_INLINE_VISIBILITY
+ explicit any(in_place_type_t<_Tp>, _Args&&... __args);
+
+ template <class _Tp, class _Up, class ..._Args,
+ class = enable_if_t<
+ is_constructible<_Tp, initializer_list<_Up>&, _Args...>::value &&
+ is_copy_constructible<_Tp>::value>
+ >
+ _LIBCPP_INLINE_VISIBILITY
+ explicit any(in_place_type_t<_Tp>, initializer_list<_Up>, _Args&&... __args);
+
+ _LIBCPP_INLINE_VISIBILITY
+ ~any() { this->reset(); }
+
+ // assignments
+ _LIBCPP_INLINE_VISIBILITY
+ any & operator=(any const & __rhs) {
+ any(__rhs).swap(*this);
+ return *this;
+ }
+
+ _LIBCPP_INLINE_VISIBILITY
+ any & operator=(any && __rhs) _NOEXCEPT {
+ any(_VSTD::move(__rhs)).swap(*this);
+ return *this;
+ }
+
+ // TODO: Should this be constrained to disallow in_place types like the
+ // ValueType constructor?
+ template <
+ class _ValueType
+ , class = enable_if_t<
+ !is_same<decay_t<_ValueType>, any>::value
+ && is_copy_constructible<_ValueType>::value
+ && !__is_inplace_type<_ValueType>::value>
+ >
+ _LIBCPP_INLINE_VISIBILITY
+ any & operator=(_ValueType && __rhs);
+
+ template <class _Tp, class ..._Args,
+ class = enable_if_t<
+ is_constructible<_Tp, _Args...>::value &&
+ is_copy_constructible<_Tp>::value>
+ >
+ _LIBCPP_INLINE_VISIBILITY
+ void emplace(_Args&&... args);
+
+ template <class _Tp, class _Up, class ..._Args,
+ class = enable_if_t<
+ is_constructible<_Tp, initializer_list<_Up>&, _Args...>::value &&
+ is_copy_constructible<_Tp>::value>
+ >
+ _LIBCPP_INLINE_VISIBILITY
+ void emplace(initializer_list<_Up>, _Args&&...);
+
+ // 6.3.3 any modifiers
+ _LIBCPP_INLINE_VISIBILITY
+ void reset() _NOEXCEPT { if (__h) this->__call(_Action::_Destroy); }
+
+ _LIBCPP_INLINE_VISIBILITY
+ void swap(any & __rhs) _NOEXCEPT;
+
+ // 6.3.4 any observers
+ _LIBCPP_INLINE_VISIBILITY
+ bool has_value() const _NOEXCEPT { return __h != nullptr; }
+
+#if !defined(_LIBCPP_NO_RTTI)
+ _LIBCPP_INLINE_VISIBILITY
+ const type_info & type() const _NOEXCEPT {
+ if (__h) {
+ return *static_cast<type_info const *>(this->__call(_Action::_TypeInfo));
+ } else {
+ return typeid(void);
+ }
+ }
+#endif
+
+private:
+ typedef __any_imp::_Action _Action;
+ using _HandleFuncPtr = void* (*)(_Action, any const *, any *, const type_info *,
+ const void* __fallback_info);
+
+ union _Storage {
+ constexpr _Storage() : __ptr(nullptr) {}
+ void * __ptr;
+ __any_imp::_Buffer __buf;
+ };
+
+ _LIBCPP_ALWAYS_INLINE
+ void * __call(_Action __a, any * __other = nullptr,
+ type_info const * __info = nullptr,
+ const void* __fallback_info = nullptr) const
+ {
+ return __h(__a, this, __other, __info, __fallback_info);
+ }
+
+ _LIBCPP_ALWAYS_INLINE
+ void * __call(_Action __a, any * __other = nullptr,
+ type_info const * __info = nullptr,
+ const void* __fallback_info = nullptr)
+ {
+ return __h(__a, this, __other, __info, __fallback_info);
+ }
+
+ template <class>
+ friend struct __any_imp::_SmallHandler;
+ template <class>
+ friend struct __any_imp::_LargeHandler;
+
+ template <class _ValueType>
+ friend add_pointer_t<add_const_t<_ValueType>>
+ any_cast(any const *) _NOEXCEPT;
+
+ template <class _ValueType>
+ friend add_pointer_t<_ValueType>
+ any_cast(any *) _NOEXCEPT;
+
+ _HandleFuncPtr __h = nullptr;
+ _Storage __s;
+};
+
+namespace __any_imp
+{
+ template <class _Tp>
+ struct _LIBCPP_TYPE_VIS_ONLY _SmallHandler
+ {
+ _LIBCPP_INLINE_VISIBILITY
+ static void* __handle(_Action __act, any const * __this, any * __other,
+ type_info const * __info, const void* __fallback_info)
+ {
+ switch (__act)
+ {
+ case _Action::_Destroy:
+ __destroy(const_cast<any &>(*__this));
+ return nullptr;
+ case _Action::_Copy:
+ __copy(*__this, *__other);
+ return nullptr;
+ case _Action::_Move:
+ __move(const_cast<any &>(*__this), *__other);
+ return nullptr;
+ case _Action::_Get:
+ return __get(const_cast<any &>(*__this), __info, __fallback_info);
+ case _Action::_TypeInfo:
+ return __type_info();
+ }
+ }
+
+ template <class ..._Args>
+ _LIBCPP_INLINE_VISIBILITY
+ static void __create(any & __dest, _Args&&... __args) {
+ ::new (static_cast<void*>(&__dest.__s.__buf)) _Tp(_VSTD::forward<_Args>(__args)...);
+ __dest.__h = &_SmallHandler::__handle;
+ }
+
+ private:
+ _LIBCPP_INLINE_VISIBILITY
+ static void __destroy(any & __this) {
+ _Tp & __value = *static_cast<_Tp *>(static_cast<void*>(&__this.__s.__buf));
+ __value.~_Tp();
+ __this.__h = nullptr;
+ }
+
+ _LIBCPP_INLINE_VISIBILITY
+ static void __copy(any const & __this, any & __dest) {
+ _SmallHandler::__create(__dest, *static_cast<_Tp const *>(
+ static_cast<void const *>(&__this.__s.__buf)));
+ }
+
+ _LIBCPP_INLINE_VISIBILITY
+ static void __move(any & __this, any & __dest) {
+ _SmallHandler::__create(__dest, _VSTD::move(
+ *static_cast<_Tp*>(static_cast<void*>(&__this.__s.__buf))));
+ __destroy(__this);
+ }
+
+ _LIBCPP_INLINE_VISIBILITY
+ static void* __get(any & __this,
+ type_info const * __info,
+ const void* __fallback_id)
+ {
+ if (__any_imp::__compare_typeid<_Tp>(__info, __fallback_id))
+ return static_cast<void*>(&__this.__s.__buf);
+ return nullptr;
+ }
+
+ _LIBCPP_INLINE_VISIBILITY
+ static void* __type_info()
+ {
+#if !defined(_LIBCPP_NO_RTTI)
+ return const_cast<void*>(static_cast<void const *>(&typeid(_Tp)));
+#else
+ return nullptr;
+#endif
+ }
+ };
+
+ template <class _Tp>
+ struct _LIBCPP_TYPE_VIS_ONLY _LargeHandler
+ {
+ _LIBCPP_INLINE_VISIBILITY
+ static void* __handle(_Action __act, any const * __this,
+ any * __other, type_info const * __info,
+ void const* __fallback_info)
+ {
+ switch (__act)
+ {
+ case _Action::_Destroy:
+ __destroy(const_cast<any &>(*__this));
+ return nullptr;
+ case _Action::_Copy:
+ __copy(*__this, *__other);
+ return nullptr;
+ case _Action::_Move:
+ __move(const_cast<any &>(*__this), *__other);
+ return nullptr;
+ case _Action::_Get:
+ return __get(const_cast<any &>(*__this), __info, __fallback_info);
+ case _Action::_TypeInfo:
+ return __type_info();
+ }
+ }
+
+ template <class ..._Args>
+ _LIBCPP_INLINE_VISIBILITY
+ static void __create(any & __dest, _Args&&... __args) {
+ typedef allocator<_Tp> _Alloc;
+ typedef __allocator_destructor<_Alloc> _Dp;
+ _Alloc __a;
+ unique_ptr<_Tp, _Dp> __hold(__a.allocate(1), _Dp(__a, 1));
+ ::new ((void*)__hold.get()) _Tp(_VSTD::forward<_Args>(__args)...);
+ __dest.__s.__ptr = __hold.release();
+ __dest.__h = &_LargeHandler::__handle;
+ }
+
+ private:
+
+ _LIBCPP_INLINE_VISIBILITY
+ static void __destroy(any & __this){
+ delete static_cast<_Tp*>(__this.__s.__ptr);
+ __this.__h = nullptr;
+ }
+
+ _LIBCPP_INLINE_VISIBILITY
+ static void __copy(any const & __this, any & __dest) {
+ _LargeHandler::__create(__dest, *static_cast<_Tp const *>(__this.__s.__ptr));
+ }
+
+ _LIBCPP_INLINE_VISIBILITY
+ static void __move(any & __this, any & __dest) {
+ __dest.__s.__ptr = __this.__s.__ptr;
+ __dest.__h = &_LargeHandler::__handle;
+ __this.__h = nullptr;
+ }
+
+ _LIBCPP_INLINE_VISIBILITY
+ static void* __get(any & __this, type_info const * __info,
+ void const* __fallback_info)
+ {
+ if (__any_imp::__compare_typeid<_Tp>(__info, __fallback_info))
+ return static_cast<void*>(__this.__s.__ptr);
+ return nullptr;
+
+ }
+
+ _LIBCPP_INLINE_VISIBILITY
+ static void* __type_info()
+ {
+#if !defined(_LIBCPP_NO_RTTI)
+ return const_cast<void*>(static_cast<void const *>(&typeid(_Tp)));
+#else
+ return nullptr;
+#endif
+ }
+ };
+
+} // namespace __any_imp
+
+
+template <class _ValueType, class>
+any::any(_ValueType && __v) : __h(nullptr)
+{
+ typedef typename decay<_ValueType>::type _Tp;
+ static_assert(is_copy_constructible<_Tp>::value,
+ "_ValueType must be CopyConstructible.");
+ using _ForwardTp = conditional_t<
+ is_move_constructible<_Tp>::value, _ValueType, _ValueType&>;
+ typedef __any_imp::_Handler<_Tp> _HandlerType;
+ _HandlerType::__create(*this, _VSTD::forward<_ForwardTp>(__v));
+}
+
+template <class _Tp, class ..._Args, class>
+any::any(in_place_type_t<_Tp>, _Args&&... __args) {
+ using _Hp = __any_imp::_Handler<_Tp>;
+ _Hp::__create(*this, _VSTD::forward<_Args>(__args)...);
+};
+
+template <class _Tp, class _Up, class ..._Args, class>
+any::any(in_place_type_t<_Tp>, initializer_list<_Up> __il, _Args&&... __args) {
+ using _Hp = __any_imp::_Handler<_Tp>;
+ _Hp::__create(*this, __il, _VSTD::forward<_Args>(__args)...);
+}
+
+template <class _ValueType, class>
+inline _LIBCPP_INLINE_VISIBILITY
+any & any::operator=(_ValueType && __v)
+{
+ typedef typename decay<_ValueType>::type _Tp;
+ static_assert(is_copy_constructible<_Tp>::value,
+ "_ValueType must be CopyConstructible.");
+ any(_VSTD::forward<_ValueType>(__v)).swap(*this);
+ return *this;
+}
+
+template <class _Tp, class ..._Args, class>
+inline _LIBCPP_INLINE_VISIBILITY
+void any::emplace(_Args&&... __args) {
+ using _Hp = __any_imp::_Handler<_Tp>;
+ reset();
+ _Hp::__create(*this, _VSTD::forward<_Args>(__args)...);
+}
+
+template <class _Tp, class _Up, class ..._Args, class>
+inline _LIBCPP_INLINE_VISIBILITY
+void any::emplace(initializer_list<_Up> __il, _Args&&... __args) {
+ using _Hp = __any_imp::_Handler<_Tp>;
+ reset();
+ _Hp::__create(*this, __il, _VSTD::forward<_Args>(__args)...);
+}
+
+inline _LIBCPP_INLINE_VISIBILITY
+void any::swap(any & __rhs) _NOEXCEPT
+{
+ if (__h && __rhs.__h) {
+ any __tmp;
+ __rhs.__call(_Action::_Move, &__tmp);
+ this->__call(_Action::_Move, &__rhs);
+ __tmp.__call(_Action::_Move, this);
+ }
+ else if (__h) {
+ this->__call(_Action::_Move, &__rhs);
+ }
+ else if (__rhs.__h) {
+ __rhs.__call(_Action::_Move, this);
+ }
+}
+
+// 6.4 Non-member functions
+
+inline _LIBCPP_INLINE_VISIBILITY
+void swap(any & __lhs, any & __rhs) _NOEXCEPT
+{
+ __lhs.swap(__rhs);
+}
+
+template <class _Tp, class ..._Args>
+inline _LIBCPP_INLINE_VISIBILITY
+any make_any(_Args&&... __args) {
+ return any(in_place<_Tp>, _VSTD::forward<_Args>(__args)...);
+}
+
+template <class _Tp, class _Up, class ..._Args>
+inline _LIBCPP_INLINE_VISIBILITY
+any make_any(initializer_list<_Up> __il, _Args&&... __args) {
+ return any(in_place<_Tp>, __il, _VSTD::forward<_Args>(__args)...);
+}
+
+template <class _ValueType>
+inline _LIBCPP_INLINE_VISIBILITY
+_ValueType any_cast(any const & __v)
+{
+ static_assert(
+ is_reference<_ValueType>::value
+ || is_copy_constructible<_ValueType>::value,
+ "_ValueType is required to be a reference or a CopyConstructible type.");
+ using _Tp = add_const_t<remove_reference_t<_ValueType>>;
+ _Tp * __tmp = _VSTD::any_cast<_Tp>(&__v);
+ if (__tmp == nullptr)
+ __libcpp_throw(bad_any_cast());
+ return *__tmp;
+}
+
+template <class _ValueType>
+inline _LIBCPP_INLINE_VISIBILITY
+_ValueType any_cast(any & __v)
+{
+ static_assert(
+ is_reference<_ValueType>::value
+ || is_copy_constructible<_ValueType>::value,
+ "_ValueType is required to be a reference or a CopyConstructible type.");
+ typedef typename remove_reference<_ValueType>::type _Tp;
+ _Tp * __tmp = _VSTD::any_cast<_Tp>(&__v);
+ if (__tmp == nullptr)
+ __libcpp_throw(bad_any_cast());
+ return *__tmp;
+}
+
+template <class _ValueType>
+inline _LIBCPP_INLINE_VISIBILITY
+_ValueType any_cast(any && __v)
+{
+ static_assert(
+ is_reference<_ValueType>::value
+ || is_copy_constructible<_ValueType>::value,
+ "_ValueType is required to be a reference or a CopyConstructible type.");
+ typedef typename remove_reference<_ValueType>::type _Tp;
+ using _ForwardTp = conditional_t<
+ is_reference<_ValueType>::value,
+ _ValueType,
+ conditional_t<is_move_constructible<_Tp>::value, _Tp, _Tp&>
+ >;
+ _Tp * __tmp = _VSTD::any_cast<_Tp>(&__v);
+ if (__tmp == nullptr)
+ __libcpp_throw(bad_any_cast());
+ return _VSTD::forward<_ForwardTp>(*__tmp);
+}
+
+template <class _ValueType>
+inline _LIBCPP_INLINE_VISIBILITY
+add_pointer_t<add_const_t<_ValueType>>
+any_cast(any const * __any) _NOEXCEPT
+{
+ static_assert(!is_reference<_ValueType>::value,
+ "_ValueType may not be a reference.");
+ return _VSTD::any_cast<_ValueType>(const_cast<any *>(__any));
+}
+
+template <class _ValueType>
+add_pointer_t<_ValueType>
+any_cast(any * __any) _NOEXCEPT
+{
+ using __any_imp::_Action;
+ static_assert(!is_reference<_ValueType>::value,
+ "_ValueType may not be a reference.");
+ typedef typename add_pointer<_ValueType>::type _ReturnType;
+ if (__any && __any->__h) {
+ return static_cast<_ReturnType>(
+ __any->__call(_Action::_Get, nullptr,
+#if !defined(_LIBCPP_NO_RTTI)
+ &typeid(_ValueType),
+#else
+ nullptr,
+#endif
+ __any_imp::__get_fallback_typeid<_ValueType>()
+ ));
+ }
+ return nullptr;
+}
+
+#endif // _LIBCPP_STD_VER > 14
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_ANY