diff options
author | Abseil Team <absl-team@google.com> | 2019-08-08 10:56:58 -0700 |
---|---|---|
committer | CJ Johnson <johnsoncj@google.com> | 2019-08-08 14:19:45 -0400 |
commit | aa844899c937bde5d2b24f276b59997e5b668bde (patch) | |
tree | cd18e64150abc74b85bbbf6abf990f66fa47cacd /absl/types/internal | |
parent | fcb104594b0bb4b8ac306cb2f55ecdad40974683 (diff) |
Creation of LTS branch "lts_2019_08_08"20190808
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GitOrigin-RevId: 9ee91d3e430fb33a4590486573792eb0fa146c2d
Change-Id: Ia06e548bc106cc9d136f6c65714be6645317aced
Diffstat (limited to 'absl/types/internal')
-rw-r--r-- | absl/types/internal/optional.h | 396 | ||||
-rw-r--r-- | absl/types/internal/span.h | 128 | ||||
-rw-r--r-- | absl/types/internal/variant.h | 74 |
3 files changed, 568 insertions, 30 deletions
diff --git a/absl/types/internal/optional.h b/absl/types/internal/optional.h new file mode 100644 index 00000000..3c8e7cca --- /dev/null +++ b/absl/types/internal/optional.h @@ -0,0 +1,396 @@ +// Copyright 2017 The Abseil Authors. +// +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// https://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. +// +#ifndef ABSL_TYPES_INTERNAL_OPTIONAL_H_ +#define ABSL_TYPES_INTERNAL_OPTIONAL_H_ + +#include <functional> +#include <new> +#include <type_traits> +#include <utility> + +#include "absl/base/internal/inline_variable.h" +#include "absl/memory/memory.h" +#include "absl/meta/type_traits.h" +#include "absl/utility/utility.h" + +// ABSL_OPTIONAL_USE_INHERITING_CONSTRUCTORS +// +// Inheriting constructors is supported in GCC 4.8+, Clang 3.3+ and MSVC 2015. +// __cpp_inheriting_constructors is a predefined macro and a recommended way to +// check for this language feature, but GCC doesn't support it until 5.0 and +// Clang doesn't support it until 3.6. +// Also, MSVC 2015 has a bug: it doesn't inherit the constexpr template +// constructor. For example, the following code won't work on MSVC 2015 Update3: +// struct Base { +// int t; +// template <typename T> +// constexpr Base(T t_) : t(t_) {} +// }; +// struct Foo : Base { +// using Base::Base; +// } +// constexpr Foo foo(0); // doesn't work on MSVC 2015 +#if defined(__clang__) +#if __has_feature(cxx_inheriting_constructors) +#define ABSL_OPTIONAL_USE_INHERITING_CONSTRUCTORS 1 +#endif +#elif (defined(__GNUC__) && \ + (__GNUC__ > 4 || __GNUC__ == 4 && __GNUC_MINOR__ >= 8)) || \ + (__cpp_inheriting_constructors >= 200802) || \ + (defined(_MSC_VER) && _MSC_VER >= 1910) +#define ABSL_OPTIONAL_USE_INHERITING_CONSTRUCTORS 1 +#endif + +namespace absl { +inline namespace lts_2019_08_08 { + +// Forward declaration +template <typename T> +class optional; + +namespace optional_internal { + +// This tag type is used as a constructor parameter type for `nullopt_t`. +struct init_t { + explicit init_t() = default; +}; + +struct empty_struct {}; + +// This class stores the data in optional<T>. +// It is specialized based on whether T is trivially destructible. +// This is the specialization for non trivially destructible type. +template <typename T, bool unused = std::is_trivially_destructible<T>::value> +class optional_data_dtor_base { + struct dummy_type { + static_assert(sizeof(T) % sizeof(empty_struct) == 0, ""); + // Use an array to avoid GCC 6 placement-new warning. + empty_struct data[sizeof(T) / sizeof(empty_struct)]; + }; + + protected: + // Whether there is data or not. + bool engaged_; + // Data storage + union { + dummy_type dummy_; + T data_; + }; + + void destruct() noexcept { + if (engaged_) { + data_.~T(); + engaged_ = false; + } + } + + // dummy_ must be initialized for constexpr constructor. + constexpr optional_data_dtor_base() noexcept : engaged_(false), dummy_{{}} {} + + template <typename... Args> + constexpr explicit optional_data_dtor_base(in_place_t, Args&&... args) + : engaged_(true), data_(absl::forward<Args>(args)...) {} + + ~optional_data_dtor_base() { destruct(); } +}; + +// Specialization for trivially destructible type. +template <typename T> +class optional_data_dtor_base<T, true> { + struct dummy_type { + static_assert(sizeof(T) % sizeof(empty_struct) == 0, ""); + // Use array to avoid GCC 6 placement-new warning. + empty_struct data[sizeof(T) / sizeof(empty_struct)]; + }; + + protected: + // Whether there is data or not. + bool engaged_; + // Data storage + union { + dummy_type dummy_; + T data_; + }; + void destruct() noexcept { engaged_ = false; } + + // dummy_ must be initialized for constexpr constructor. + constexpr optional_data_dtor_base() noexcept : engaged_(false), dummy_{{}} {} + + template <typename... Args> + constexpr explicit optional_data_dtor_base(in_place_t, Args&&... args) + : engaged_(true), data_(absl::forward<Args>(args)...) {} +}; + +template <typename T> +class optional_data_base : public optional_data_dtor_base<T> { + protected: + using base = optional_data_dtor_base<T>; +#ifdef ABSL_OPTIONAL_USE_INHERITING_CONSTRUCTORS + using base::base; +#else + optional_data_base() = default; + + template <typename... Args> + constexpr explicit optional_data_base(in_place_t t, Args&&... args) + : base(t, absl::forward<Args>(args)...) {} +#endif + + template <typename... Args> + void construct(Args&&... args) { + // Use dummy_'s address to work around casting cv-qualified T* to void*. + ::new (static_cast<void*>(&this->dummy_)) T(std::forward<Args>(args)...); + this->engaged_ = true; + } + + template <typename U> + void assign(U&& u) { + if (this->engaged_) { + this->data_ = std::forward<U>(u); + } else { + construct(std::forward<U>(u)); + } + } +}; + +// TODO(absl-team): Add another class using +// std::is_trivially_move_constructible trait when available to match +// http://cplusplus.github.io/LWG/lwg-defects.html#2900, for types that +// have trivial move but nontrivial copy. +// Also, we should be checking is_trivially_copyable here, which is not +// supported now, so we use is_trivially_* traits instead. +template <typename T, + bool unused = absl::is_trivially_copy_constructible<T>::value&& + absl::is_trivially_copy_assignable<typename std::remove_cv< + T>::type>::value&& std::is_trivially_destructible<T>::value> +class optional_data; + +// Trivially copyable types +template <typename T> +class optional_data<T, true> : public optional_data_base<T> { + protected: +#ifdef ABSL_OPTIONAL_USE_INHERITING_CONSTRUCTORS + using optional_data_base<T>::optional_data_base; +#else + optional_data() = default; + + template <typename... Args> + constexpr explicit optional_data(in_place_t t, Args&&... args) + : optional_data_base<T>(t, absl::forward<Args>(args)...) {} +#endif +}; + +template <typename T> +class optional_data<T, false> : public optional_data_base<T> { + protected: +#ifdef ABSL_OPTIONAL_USE_INHERITING_CONSTRUCTORS + using optional_data_base<T>::optional_data_base; +#else + template <typename... Args> + constexpr explicit optional_data(in_place_t t, Args&&... args) + : optional_data_base<T>(t, absl::forward<Args>(args)...) {} +#endif + + optional_data() = default; + + optional_data(const optional_data& rhs) : optional_data_base<T>() { + if (rhs.engaged_) { + this->construct(rhs.data_); + } + } + + optional_data(optional_data&& rhs) noexcept( + absl::default_allocator_is_nothrow::value || + std::is_nothrow_move_constructible<T>::value) + : optional_data_base<T>() { + if (rhs.engaged_) { + this->construct(std::move(rhs.data_)); + } + } + + optional_data& operator=(const optional_data& rhs) { + if (rhs.engaged_) { + this->assign(rhs.data_); + } else { + this->destruct(); + } + return *this; + } + + optional_data& operator=(optional_data&& rhs) noexcept( + std::is_nothrow_move_assignable<T>::value&& + std::is_nothrow_move_constructible<T>::value) { + if (rhs.engaged_) { + this->assign(std::move(rhs.data_)); + } else { + this->destruct(); + } + return *this; + } +}; + +// Ordered by level of restriction, from low to high. +// Copyable implies movable. +enum class copy_traits { copyable = 0, movable = 1, non_movable = 2 }; + +// Base class for enabling/disabling copy/move constructor. +template <copy_traits> +class optional_ctor_base; + +template <> +class optional_ctor_base<copy_traits::copyable> { + public: + constexpr optional_ctor_base() = default; + optional_ctor_base(const optional_ctor_base&) = default; + optional_ctor_base(optional_ctor_base&&) = default; + optional_ctor_base& operator=(const optional_ctor_base&) = default; + optional_ctor_base& operator=(optional_ctor_base&&) = default; +}; + +template <> +class optional_ctor_base<copy_traits::movable> { + public: + constexpr optional_ctor_base() = default; + optional_ctor_base(const optional_ctor_base&) = delete; + optional_ctor_base(optional_ctor_base&&) = default; + optional_ctor_base& operator=(const optional_ctor_base&) = default; + optional_ctor_base& operator=(optional_ctor_base&&) = default; +}; + +template <> +class optional_ctor_base<copy_traits::non_movable> { + public: + constexpr optional_ctor_base() = default; + optional_ctor_base(const optional_ctor_base&) = delete; + optional_ctor_base(optional_ctor_base&&) = delete; + optional_ctor_base& operator=(const optional_ctor_base&) = default; + optional_ctor_base& operator=(optional_ctor_base&&) = default; +}; + +// Base class for enabling/disabling copy/move assignment. +template <copy_traits> +class optional_assign_base; + +template <> +class optional_assign_base<copy_traits::copyable> { + public: + constexpr optional_assign_base() = default; + optional_assign_base(const optional_assign_base&) = default; + optional_assign_base(optional_assign_base&&) = default; + optional_assign_base& operator=(const optional_assign_base&) = default; + optional_assign_base& operator=(optional_assign_base&&) = default; +}; + +template <> +class optional_assign_base<copy_traits::movable> { + public: + constexpr optional_assign_base() = default; + optional_assign_base(const optional_assign_base&) = default; + optional_assign_base(optional_assign_base&&) = default; + optional_assign_base& operator=(const optional_assign_base&) = delete; + optional_assign_base& operator=(optional_assign_base&&) = default; +}; + +template <> +class optional_assign_base<copy_traits::non_movable> { + public: + constexpr optional_assign_base() = default; + optional_assign_base(const optional_assign_base&) = default; + optional_assign_base(optional_assign_base&&) = default; + optional_assign_base& operator=(const optional_assign_base&) = delete; + optional_assign_base& operator=(optional_assign_base&&) = delete; +}; + +template <typename T> +struct ctor_copy_traits { + static constexpr copy_traits traits = + std::is_copy_constructible<T>::value + ? copy_traits::copyable + : std::is_move_constructible<T>::value ? copy_traits::movable + : copy_traits::non_movable; +}; + +template <typename T> +struct assign_copy_traits { + static constexpr copy_traits traits = + absl::is_copy_assignable<T>::value && std::is_copy_constructible<T>::value + ? copy_traits::copyable + : absl::is_move_assignable<T>::value && + std::is_move_constructible<T>::value + ? copy_traits::movable + : copy_traits::non_movable; +}; + +// Whether T is constructible or convertible from optional<U>. +template <typename T, typename U> +struct is_constructible_convertible_from_optional + : std::integral_constant< + bool, std::is_constructible<T, optional<U>&>::value || + std::is_constructible<T, optional<U>&&>::value || + std::is_constructible<T, const optional<U>&>::value || + std::is_constructible<T, const optional<U>&&>::value || + std::is_convertible<optional<U>&, T>::value || + std::is_convertible<optional<U>&&, T>::value || + std::is_convertible<const optional<U>&, T>::value || + std::is_convertible<const optional<U>&&, T>::value> {}; + +// Whether T is constructible or convertible or assignable from optional<U>. +template <typename T, typename U> +struct is_constructible_convertible_assignable_from_optional + : std::integral_constant< + bool, is_constructible_convertible_from_optional<T, U>::value || + std::is_assignable<T&, optional<U>&>::value || + std::is_assignable<T&, optional<U>&&>::value || + std::is_assignable<T&, const optional<U>&>::value || + std::is_assignable<T&, const optional<U>&&>::value> {}; + +// Helper function used by [optional.relops], [optional.comp_with_t], +// for checking whether an expression is convertible to bool. +bool convertible_to_bool(bool); + +// Base class for std::hash<absl::optional<T>>: +// If std::hash<std::remove_const_t<T>> is enabled, it provides operator() to +// compute the hash; Otherwise, it is disabled. +// Reference N4659 23.14.15 [unord.hash]. +template <typename T, typename = size_t> +struct optional_hash_base { + optional_hash_base() = delete; + optional_hash_base(const optional_hash_base&) = delete; + optional_hash_base(optional_hash_base&&) = delete; + optional_hash_base& operator=(const optional_hash_base&) = delete; + optional_hash_base& operator=(optional_hash_base&&) = delete; +}; + +template <typename T> +struct optional_hash_base<T, decltype(std::hash<absl::remove_const_t<T> >()( + std::declval<absl::remove_const_t<T> >()))> { + using argument_type = absl::optional<T>; + using result_type = size_t; + size_t operator()(const absl::optional<T>& opt) const { + absl::type_traits_internal::AssertHashEnabled<absl::remove_const_t<T>>(); + if (opt) { + return std::hash<absl::remove_const_t<T> >()(*opt); + } else { + return static_cast<size_t>(0x297814aaad196e6dULL); + } + } +}; + +} // namespace optional_internal +} // inline namespace lts_2019_08_08 +} // namespace absl + +#undef ABSL_OPTIONAL_USE_INHERITING_CONSTRUCTORS + +#endif // ABSL_TYPES_INTERNAL_OPTIONAL_H_ diff --git a/absl/types/internal/span.h b/absl/types/internal/span.h new file mode 100644 index 00000000..873ae160 --- /dev/null +++ b/absl/types/internal/span.h @@ -0,0 +1,128 @@ +// +// Copyright 2019 The Abseil Authors. +// +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// https://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. +// +#ifndef ABSL_TYPES_INTERNAL_SPAN_H_ +#define ABSL_TYPES_INTERNAL_SPAN_H_ + +#include <algorithm> +#include <cstddef> +#include <string> +#include <type_traits> + +#include "absl/algorithm/algorithm.h" +#include "absl/base/internal/throw_delegate.h" +#include "absl/meta/type_traits.h" + +namespace absl { +inline namespace lts_2019_08_08 { + +namespace span_internal { +// A constexpr min function +constexpr size_t Min(size_t a, size_t b) noexcept { return a < b ? a : b; } + +// Wrappers for access to container data pointers. +template <typename C> +constexpr auto GetDataImpl(C& c, char) noexcept // NOLINT(runtime/references) + -> decltype(c.data()) { + return c.data(); +} + +// Before C++17, std::string::data returns a const char* in all cases. +inline char* GetDataImpl(std::string& s, // NOLINT(runtime/references) + int) noexcept { + return &s[0]; +} + +template <typename C> +constexpr auto GetData(C& c) noexcept // NOLINT(runtime/references) + -> decltype(GetDataImpl(c, 0)) { + return GetDataImpl(c, 0); +} + +// Detection idioms for size() and data(). +template <typename C> +using HasSize = + std::is_integral<absl::decay_t<decltype(std::declval<C&>().size())>>; + +// We want to enable conversion from vector<T*> to Span<const T* const> but +// disable conversion from vector<Derived> to Span<Base>. Here we use +// the fact that U** is convertible to Q* const* if and only if Q is the same +// type or a more cv-qualified version of U. We also decay the result type of +// data() to avoid problems with classes which have a member function data() +// which returns a reference. +template <typename T, typename C> +using HasData = + std::is_convertible<absl::decay_t<decltype(GetData(std::declval<C&>()))>*, + T* const*>; + +// Extracts value type from a Container +template <typename C> +struct ElementType { + using type = typename absl::remove_reference_t<C>::value_type; +}; + +template <typename T, size_t N> +struct ElementType<T (&)[N]> { + using type = T; +}; + +template <typename C> +using ElementT = typename ElementType<C>::type; + +template <typename T> +using EnableIfMutable = + typename std::enable_if<!std::is_const<T>::value, int>::type; + +template <template <typename> class SpanT, typename T> +bool EqualImpl(SpanT<T> a, SpanT<T> b) { + static_assert(std::is_const<T>::value, ""); + return absl::equal(a.begin(), a.end(), b.begin(), b.end()); +} + +template <template <typename> class SpanT, typename T> +bool LessThanImpl(SpanT<T> a, SpanT<T> b) { + // We can't use value_type since that is remove_cv_t<T>, so we go the long way + // around. + static_assert(std::is_const<T>::value, ""); + return std::lexicographical_compare(a.begin(), a.end(), b.begin(), b.end()); +} + +// The `IsConvertible` classes here are needed because of the +// `std::is_convertible` bug in libcxx when compiled with GCC. This build +// configuration is used by Android NDK toolchain. Reference link: +// https://bugs.llvm.org/show_bug.cgi?id=27538. +template <typename From, typename To> +struct IsConvertibleHelper { + private: + static std::true_type testval(To); + static std::false_type testval(...); + + public: + using type = decltype(testval(std::declval<From>())); +}; + +template <typename From, typename To> +struct IsConvertible : IsConvertibleHelper<From, To>::type {}; + +// TODO(zhangxy): replace `IsConvertible` with `std::is_convertible` once the +// older version of libcxx is not supported. +template <typename From, typename To> +using EnableIfConvertibleTo = + typename std::enable_if<IsConvertible<From, To>::value>::type; +} // namespace span_internal +} // inline namespace lts_2019_08_08 +} // namespace absl + +#endif // ABSL_TYPES_INTERNAL_SPAN_H_ diff --git a/absl/types/internal/variant.h b/absl/types/internal/variant.h index 875f88e0..4f29f617 100644 --- a/absl/types/internal/variant.h +++ b/absl/types/internal/variant.h @@ -4,7 +4,7 @@ // you may not use this file except in compliance with the License. // You may obtain a copy of the License at // -// http://www.apache.org/licenses/LICENSE-2.0 +// https://www.apache.org/licenses/LICENSE-2.0 // // Unless required by applicable law or agreed to in writing, software // distributed under the License is distributed on an "AS IS" BASIS, @@ -15,7 +15,6 @@ // Implementation details of absl/types/variant.h, pulled into a // separate file to avoid cluttering the top of the API header with // implementation details. -// #ifndef ABSL_TYPES_variant_internal_H_ #define ABSL_TYPES_variant_internal_H_ @@ -41,7 +40,7 @@ #if !defined(ABSL_HAVE_STD_VARIANT) namespace absl { -inline namespace lts_2018_12_18 { +inline namespace lts_2019_08_08 { template <class... Types> class variant; @@ -206,7 +205,7 @@ template <class Op, class... Vs> using VisitIndicesResultT = typename VisitIndicesResultImpl<Op, Vs...>::type; template <class ReturnType, class FunctionObject, class EndIndices, - std::size_t... BoundIndices> + class BoundIndices> struct MakeVisitationMatrix; template <class ReturnType, class FunctionObject, std::size_t... Indices> @@ -220,7 +219,7 @@ constexpr ReturnType call_with_indices(FunctionObject&& function) { template <class ReturnType, class FunctionObject, std::size_t... BoundIndices> struct MakeVisitationMatrix<ReturnType, FunctionObject, index_sequence<>, - BoundIndices...> { + index_sequence<BoundIndices...>> { using ResultType = ReturnType (*)(FunctionObject&&); static constexpr ResultType Run() { return &call_with_indices<ReturnType, FunctionObject, @@ -228,24 +227,34 @@ struct MakeVisitationMatrix<ReturnType, FunctionObject, index_sequence<>, } }; +template <typename Is, std::size_t J> +struct AppendToIndexSequence; + +template <typename Is, std::size_t J> +using AppendToIndexSequenceT = typename AppendToIndexSequence<Is, J>::type; + +template <std::size_t... Is, std::size_t J> +struct AppendToIndexSequence<index_sequence<Is...>, J> { + using type = index_sequence<Is..., J>; +}; + template <class ReturnType, class FunctionObject, class EndIndices, - class CurrIndices, std::size_t... BoundIndices> + class CurrIndices, class BoundIndices> struct MakeVisitationMatrixImpl; -template <class ReturnType, class FunctionObject, std::size_t... EndIndices, - std::size_t... CurrIndices, std::size_t... BoundIndices> -struct MakeVisitationMatrixImpl< - ReturnType, FunctionObject, index_sequence<EndIndices...>, - index_sequence<CurrIndices...>, BoundIndices...> { +template <class ReturnType, class FunctionObject, class EndIndices, + std::size_t... CurrIndices, class BoundIndices> +struct MakeVisitationMatrixImpl<ReturnType, FunctionObject, EndIndices, + index_sequence<CurrIndices...>, BoundIndices> { using ResultType = SimpleArray< - typename MakeVisitationMatrix<ReturnType, FunctionObject, - index_sequence<EndIndices...>>::ResultType, + typename MakeVisitationMatrix<ReturnType, FunctionObject, EndIndices, + index_sequence<>>::ResultType, sizeof...(CurrIndices)>; static constexpr ResultType Run() { - return {{MakeVisitationMatrix<ReturnType, FunctionObject, - index_sequence<EndIndices...>, - BoundIndices..., CurrIndices>::Run()...}}; + return {{MakeVisitationMatrix< + ReturnType, FunctionObject, EndIndices, + AppendToIndexSequenceT<BoundIndices, CurrIndices>>::Run()...}}; } }; @@ -253,10 +262,11 @@ template <class ReturnType, class FunctionObject, std::size_t HeadEndIndex, std::size_t... TailEndIndices, std::size_t... BoundIndices> struct MakeVisitationMatrix<ReturnType, FunctionObject, index_sequence<HeadEndIndex, TailEndIndices...>, - BoundIndices...> - : MakeVisitationMatrixImpl< - ReturnType, FunctionObject, index_sequence<TailEndIndices...>, - absl::make_index_sequence<HeadEndIndex>, BoundIndices...> {}; + index_sequence<BoundIndices...>> + : MakeVisitationMatrixImpl<ReturnType, FunctionObject, + index_sequence<TailEndIndices...>, + absl::make_index_sequence<HeadEndIndex>, + index_sequence<BoundIndices...>> {}; struct UnreachableSwitchCase { template <class Op> @@ -425,7 +435,8 @@ struct VisitIndicesFallback { static VisitIndicesResultT<Op, SizeT...> Run(Op&& op, SizeT... indices) { return AccessSimpleArray( MakeVisitationMatrix<VisitIndicesResultT<Op, SizeT...>, Op, - index_sequence<(EndIndices + 1)...>>::Run(), + index_sequence<(EndIndices + 1)...>, + index_sequence<>>::Run(), (indices + 1)...)(absl::forward<Op>(op)); } }; @@ -839,8 +850,8 @@ struct ImaginaryFun<variant<H, T...>, I> : ImaginaryFun<variant<T...>, I + 1> { // NOTE: const& and && are used instead of by-value due to lack of guaranteed // move elision of C++17. This may have other minor differences, but tests // pass. - static SizeT<I> Run(const H&); - static SizeT<I> Run(H&&); + static SizeT<I> Run(const H&, SizeT<I>); + static SizeT<I> Run(H&&, SizeT<I>); }; // The following metafunctions are used in constructor and assignment @@ -862,7 +873,8 @@ struct ConversionIsPossibleImpl : std::false_type {}; template <class Variant, class T> struct ConversionIsPossibleImpl< - Variant, T, void_t<decltype(ImaginaryFun<Variant>::Run(std::declval<T>()))>> + Variant, T, + void_t<decltype(ImaginaryFun<Variant>::Run(std::declval<T>(), {}))>> : std::true_type {}; template <class Variant, class T> @@ -870,8 +882,9 @@ struct ConversionIsPossible : ConversionIsPossibleImpl<Variant, T>::type {}; template <class Variant, class T> struct IndexOfConstructedType< - Variant, T, void_t<decltype(ImaginaryFun<Variant>::Run(std::declval<T>()))>> - : decltype(ImaginaryFun<Variant>::Run(std::declval<T>())) {}; + Variant, T, + void_t<decltype(ImaginaryFun<Variant>::Run(std::declval<T>(), {}))>> + : decltype(ImaginaryFun<Variant>::Run(std::declval<T>(), {})) {}; template <std::size_t... Is> struct ContainsVariantNPos @@ -1550,8 +1563,8 @@ struct SwapSameIndex { variant<Types...>* w; template <std::size_t I> void operator()(SizeT<I>) const { - using std::swap; - swap(VariantCoreAccess::Access<I>(*v), VariantCoreAccess::Access<I>(*w)); + type_traits_internal::Swap(VariantCoreAccess::Access<I>(*v), + VariantCoreAccess::Access<I>(*w)); } void operator()(SizeT<variant_npos>) const {} @@ -1606,11 +1619,12 @@ struct VariantHashVisitor { template <typename Variant, typename... Ts> struct VariantHashBase<Variant, absl::enable_if_t<absl::conjunction< - type_traits_internal::IsHashEnabled<Ts>...>::value>, + type_traits_internal::IsHashable<Ts>...>::value>, Ts...> { using argument_type = Variant; using result_type = size_t; size_t operator()(const Variant& var) const { + type_traits_internal::AssertHashEnabled<Ts...>(); if (var.valueless_by_exception()) { return 239799884; } @@ -1625,7 +1639,7 @@ struct VariantHashBase<Variant, }; } // namespace variant_internal -} // inline namespace lts_2018_12_18 +} // inline namespace lts_2019_08_08 } // namespace absl #endif // !defined(ABSL_HAVE_STD_VARIANT) |