From b655b8fc7eb4af02231fa0105dddd90a8cfceea1 Mon Sep 17 00:00:00 2001 From: Jonathan Wakely Date: Mon, 20 Aug 2018 13:13:25 +0100 Subject: [PATCH] Refactor std::optional SFINAE constraints * include/std/optional (_Optional_payload): Use variable templates for conditions in default template arguments and exception specifications. (optional): Likewise. Adjust indentation. (optional::__not_self, optional::__not_tag, optional::_Requires): New SFINAE helpers. (optional::optional): Use new helpers in constructor constraints. * include/std/type_traits (__or_v, __and_v): New variable templates. * testsuite/20_util/optional/cons/value_neg.cc: Change dg-error to dg-prune-output. Remove unused header. From-SVN: r263657 --- libstdc++-v3/ChangeLog | 13 + libstdc++-v3/include/std/optional | 340 +++++++++--------- libstdc++-v3/include/std/type_traits | 5 + .../20_util/optional/cons/value_neg.cc | 6 +- 4 files changed, 187 insertions(+), 177 deletions(-) diff --git a/libstdc++-v3/ChangeLog b/libstdc++-v3/ChangeLog index 3736456b716..39855d9b691 100644 --- a/libstdc++-v3/ChangeLog +++ b/libstdc++-v3/ChangeLog @@ -1,3 +1,16 @@ +2018-08-20 Jonathan Wakely + + * include/std/optional (_Optional_payload): Use variable templates + for conditions in default template arguments and exception + specifications. + (optional): Likewise. Adjust indentation. + (optional::__not_self, optional::__not_tag, optional::_Requires): New + SFINAE helpers. + (optional::optional): Use new helpers in constructor constraints. + * include/std/type_traits (__or_v, __and_v): New variable templates. + * testsuite/20_util/optional/cons/value_neg.cc: Change dg-error to + dg-prune-output. Remove unused header. + 2018-08-18 François Dumont * testsuite/25_algorithms/copy/86658.cc: Use dg-options to define diff --git a/libstdc++-v3/include/std/optional b/libstdc++-v3/include/std/optional index 746ee2fd87e..d0257c07e1f 100644 --- a/libstdc++-v3/include/std/optional +++ b/libstdc++-v3/include/std/optional @@ -102,11 +102,11 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION // Payload for optionals with non-trivial destructor. template ::value, + is_trivially_destructible_v<_Tp>, bool /*_HasTrivialCopyAssignment*/ = - is_trivially_copy_assignable<_Tp>::value, + is_trivially_copy_assignable_v<_Tp>, bool /*_HasTrivialMoveAssignment*/ = - is_trivially_move_assignable<_Tp>::value> + is_trivially_move_assignable_v<_Tp>> struct _Optional_payload { constexpr _Optional_payload() noexcept : _M_empty() { } @@ -165,8 +165,8 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION _Optional_payload& operator=(_Optional_payload&& __other) - noexcept(__and_, - is_nothrow_move_assignable<_Tp>>()) + noexcept(__and_v, + is_nothrow_move_assignable<_Tp>>) { if (this->_M_engaged && __other._M_engaged) this->_M_get() = std::move(__other._M_get()); @@ -199,7 +199,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION template void _M_construct(_Args&&... __args) - noexcept(is_nothrow_constructible<_Stored_type, _Args...>()) + noexcept(is_nothrow_constructible_v<_Stored_type, _Args...>) { ::new ((void *) std::__addressof(this->_M_payload)) _Stored_type(std::forward<_Args>(__args)...); @@ -377,7 +377,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION template void _M_construct(_Args&&... __args) - noexcept(is_nothrow_constructible<_Stored_type, _Args...>()) + noexcept(is_nothrow_constructible_v<_Stored_type, _Args...>) { ::new ((void *) std::__addressof(this->_M_payload)) _Stored_type(std::forward<_Args>(__args)...); @@ -468,8 +468,8 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION _Optional_payload& operator=(_Optional_payload&& __other) - noexcept(__and_, - is_nothrow_move_assignable<_Tp>>()) + noexcept(__and_v, + is_nothrow_move_assignable<_Tp>>) { if (this->_M_engaged && __other._M_engaged) this->_M_get() = std::move(__other._M_get()); @@ -496,7 +496,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION template void _M_construct(_Args&&... __args) - noexcept(is_nothrow_constructible<_Stored_type, _Args...>()) + noexcept(is_nothrow_constructible_v<_Stored_type, _Args...>) { ::new ((void *) std::__addressof(this->_M_payload)) _Stored_type(std::forward<_Args>(__args)...); @@ -598,8 +598,8 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION _Optional_payload& operator=(_Optional_payload&& __other) - noexcept(__and_, - is_nothrow_move_assignable<_Tp>>()) + noexcept(__and_v, + is_nothrow_move_assignable<_Tp>>) { if (this->_M_engaged && __other._M_engaged) this->_M_get() = std::move(__other._M_get()); @@ -626,7 +626,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION template void _M_construct(_Args&&... __args) - noexcept(is_nothrow_constructible<_Stored_type, _Args...>()) + noexcept(is_nothrow_constructible_v<_Stored_type, _Args...>) { ::new ((void *) std::__addressof(this->_M_payload)) _Stored_type(std::forward<_Args>(__args)...); @@ -665,7 +665,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION template void _M_construct(_Args&&... __args) - noexcept(is_nothrow_constructible<_Stored_type, _Args...>()) + noexcept(is_nothrow_constructible_v<_Stored_type, _Args...>) { ::new (std::__addressof(static_cast<_Dp*>(this)->_M_payload._M_payload)) @@ -735,7 +735,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION { } constexpr _Optional_base(_Optional_base&& __other) - noexcept(is_nothrow_move_constructible<_Tp>()) + noexcept(is_nothrow_move_constructible_v<_Tp>) : _M_payload(__other._M_payload._M_engaged, std::move(__other._M_payload)) { } @@ -864,7 +864,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION constexpr _Optional_base(const _Optional_base& __other) = default; constexpr _Optional_base(_Optional_base&& __other) - noexcept(is_nothrow_move_constructible<_Tp>()) + noexcept(is_nothrow_move_constructible_v<_Tp>) : _M_payload(__other._M_payload._M_engaged, std::move(__other._M_payload)) { } @@ -985,16 +985,16 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION class optional : private _Optional_base<_Tp>, private _Enable_copy_move< - // Copy constructor. - is_copy_constructible<_Tp>::value, - // Copy assignment. - __and_, is_copy_assignable<_Tp>>::value, - // Move constructor. - is_move_constructible<_Tp>::value, - // Move assignment. - __and_, is_move_assignable<_Tp>>::value, - // Unique tag type. - optional<_Tp>> + // Copy constructor. + is_copy_constructible_v<_Tp>, + // Copy assignment. + __and_v, is_copy_assignable<_Tp>>, + // Move constructor. + is_move_constructible_v<_Tp>, + // Move assignment. + __and_v, is_move_assignable<_Tp>>, + // Unique tag type. + optional<_Tp>> { static_assert(!is_same_v, nullopt_t>); static_assert(!is_same_v, in_place_t>); @@ -1003,6 +1003,14 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION private: using _Base = _Optional_base<_Tp>; + // SFINAE helpers + template + using __not_self = __not_>>; + template + using __not_tag = __not_>>; + template + using _Requires = enable_if_t<__and_v<_Cond...>, bool>; + public: using value_type = _Tp; @@ -1011,171 +1019,158 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION constexpr optional(nullopt_t) noexcept { } // Converting constructors for engaged optionals. - template , decay_t<_Up>>>, - __not_>>, - is_constructible<_Tp, _Up&&>, - is_convertible<_Up&&, _Tp> - >::value, bool> = true> - constexpr optional(_Up&& __t) - : _Base(std::in_place, std::forward<_Up>(__t)) { } - - template , decay_t<_Up>>>, - __not_>>, - is_constructible<_Tp, _Up&&>, - __not_> - >::value, bool> = false> - explicit constexpr optional(_Up&& __t) + template, __not_tag<_Up>, + is_constructible<_Tp, _Up&&>, + is_convertible<_Up&&, _Tp>> = true> + constexpr + optional(_Up&& __t) + : _Base(std::in_place, std::forward<_Up>(__t)) { } + + template, __not_tag<_Up>, + is_constructible<_Tp, _Up&&>, + __not_>> = false> + explicit constexpr + optional(_Up&& __t) : _Base(std::in_place, std::forward<_Up>(__t)) { } - template >, - is_constructible<_Tp, const _Up&>, - is_convertible, - __not_<__converts_from_optional<_Tp, _Up>> - >::value, bool> = true> - constexpr optional(const optional<_Up>& __t) - { - if (__t) - emplace(*__t); - } + template>, + is_constructible<_Tp, const _Up&>, + is_convertible, + __not_<__converts_from_optional<_Tp, _Up>>> = true> + constexpr + optional(const optional<_Up>& __t) + { + if (__t) + emplace(*__t); + } - template >, - is_constructible<_Tp, const _Up&>, - __not_>, - __not_<__converts_from_optional<_Tp, _Up>> - >::value, bool> = false> - explicit constexpr optional(const optional<_Up>& __t) - { - if (__t) - emplace(*__t); - } + template>, + is_constructible<_Tp, const _Up&>, + __not_>, + __not_<__converts_from_optional<_Tp, _Up>>> = false> + explicit constexpr + optional(const optional<_Up>& __t) + { + if (__t) + emplace(*__t); + } template >, - is_constructible<_Tp, _Up&&>, - is_convertible<_Up&&, _Tp>, - __not_<__converts_from_optional<_Tp, _Up>> - >::value, bool> = true> - constexpr optional(optional<_Up>&& __t) - { - if (__t) - emplace(std::move(*__t)); - } + _Requires<__not_>, + is_constructible<_Tp, _Up&&>, + is_convertible<_Up&&, _Tp>, + __not_<__converts_from_optional<_Tp, _Up>>> = true> + constexpr + optional(optional<_Up>&& __t) + { + if (__t) + emplace(std::move(*__t)); + } template >, - is_constructible<_Tp, _Up&&>, - __not_>, - __not_<__converts_from_optional<_Tp, _Up>> - >::value, bool> = false> - explicit constexpr optional(optional<_Up>&& __t) - { - if (__t) - emplace(std::move(*__t)); - } + _Requires<__not_>, + is_constructible<_Tp, _Up&&>, + __not_>, + __not_<__converts_from_optional<_Tp, _Up>>> = false> + explicit constexpr + optional(optional<_Up>&& __t) + { + if (__t) + emplace(std::move(*__t)); + } template, bool> = false> - explicit constexpr optional(in_place_t, _Args&&... __args) - : _Base(std::in_place, std::forward<_Args>(__args)...) { } + _Requires> = false> + explicit constexpr + optional(in_place_t, _Args&&... __args) + : _Base(std::in_place, std::forward<_Args>(__args)...) { } template&, - _Args&&...>, bool> = false> - explicit constexpr optional(in_place_t, - initializer_list<_Up> __il, - _Args&&... __args) - : _Base(std::in_place, __il, std::forward<_Args>(__args)...) { } + _Requires&, + _Args&&...>> = false> + explicit constexpr + optional(in_place_t, initializer_list<_Up> __il, _Args&&... __args) + : _Base(std::in_place, __il, std::forward<_Args>(__args)...) { } // Assignment operators. optional& operator=(nullopt_t) noexcept { - this->_M_reset(); - return *this; + this->_M_reset(); + return *this; } template - enable_if_t<__and_< - __not_, decay_t<_Up>>>, - is_constructible<_Tp, _Up>, - __not_<__and_, - is_same<_Tp, decay_t<_Up>>>>, - is_assignable<_Tp&, _Up>>::value, + enable_if_t<__and_v<__not_self<_Up>, + __not_<__and_, + is_same<_Tp, decay_t<_Up>>>>, + is_constructible<_Tp, _Up>, + is_assignable<_Tp&, _Up>>, optional&> - operator=(_Up&& __u) - { - if (this->_M_is_engaged()) - this->_M_get() = std::forward<_Up>(__u); - else - this->_M_construct(std::forward<_Up>(__u)); + operator=(_Up&& __u) + { + if (this->_M_is_engaged()) + this->_M_get() = std::forward<_Up>(__u); + else + this->_M_construct(std::forward<_Up>(__u)); - return *this; - } + return *this; + } template - enable_if_t<__and_< - __not_>, - is_constructible<_Tp, const _Up&>, - is_assignable<_Tp&, _Up>, - __not_<__converts_from_optional<_Tp, _Up>>, - __not_<__assigns_from_optional<_Tp, _Up>> - >::value, + enable_if_t<__and_v<__not_>, + is_constructible<_Tp, const _Up&>, + is_assignable<_Tp&, _Up>, + __not_<__converts_from_optional<_Tp, _Up>>, + __not_<__assigns_from_optional<_Tp, _Up>>>, optional&> - operator=(const optional<_Up>& __u) - { - if (__u) - { - if (this->_M_is_engaged()) - this->_M_get() = *__u; - else - this->_M_construct(*__u); - } - else - { - this->_M_reset(); - } - return *this; - } + operator=(const optional<_Up>& __u) + { + if (__u) + { + if (this->_M_is_engaged()) + this->_M_get() = *__u; + else + this->_M_construct(*__u); + } + else + { + this->_M_reset(); + } + return *this; + } template - enable_if_t<__and_< - __not_>, - is_constructible<_Tp, _Up>, - is_assignable<_Tp&, _Up>, - __not_<__converts_from_optional<_Tp, _Up>>, - __not_<__assigns_from_optional<_Tp, _Up>> - >::value, + enable_if_t<__and_v<__not_>, + is_constructible<_Tp, _Up>, + is_assignable<_Tp&, _Up>, + __not_<__converts_from_optional<_Tp, _Up>>, + __not_<__assigns_from_optional<_Tp, _Up>>>, optional&> - operator=(optional<_Up>&& __u) - { - if (__u) - { - if (this->_M_is_engaged()) - this->_M_get() = std::move(*__u); - else - this->_M_construct(std::move(*__u)); - } - else - { - this->_M_reset(); - } - - return *this; - } + operator=(optional<_Up>&& __u) + { + if (__u) + { + if (this->_M_is_engaged()) + this->_M_get() = std::move(*__u); + else + this->_M_construct(std::move(*__u)); + } + else + { + this->_M_reset(); + } + + return *this; + } template - enable_if_t::value, _Tp&> + enable_if_t, _Tp&> emplace(_Args&&... __args) { this->_M_reset(); @@ -1184,8 +1179,8 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION } template - enable_if_t&, - _Args&&...>::value, _Tp&> + enable_if_t&, + _Args&&...>, _Tp&> emplace(initializer_list<_Up> __il, _Args&&... __args) { this->_M_reset(); @@ -1198,19 +1193,19 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION // Swap. void swap(optional& __other) - noexcept(is_nothrow_move_constructible<_Tp>() - && is_nothrow_swappable_v<_Tp>) + noexcept(is_nothrow_move_constructible_v<_Tp> + && is_nothrow_swappable_v<_Tp>) { - using std::swap; + using std::swap; - if (this->_M_is_engaged() && __other._M_is_engaged()) - swap(this->_M_get(), __other._M_get()); - else if (this->_M_is_engaged()) + if (this->_M_is_engaged() && __other._M_is_engaged()) + swap(this->_M_get(), __other._M_get()); + else if (this->_M_is_engaged()) { __other._M_construct(std::move(this->_M_get())); this->_M_destruct(); } - else if (__other._M_is_engaged()) + else if (__other._M_is_engaged()) { this->_M_construct(std::move(__other._M_get())); __other._M_destruct(); @@ -1307,12 +1302,13 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION ? std::move(this->_M_get()) : static_cast<_Tp>(std::forward<_Up>(__u)); } + void reset() noexcept { this->_M_reset(); } }; template using __optional_relop_t = - enable_if_t::value, bool>; + enable_if_t::value, bool>; // Comparisons between optional values. template diff --git a/libstdc++-v3/include/std/type_traits b/libstdc++-v3/include/std/type_traits index 4f89723d468..86b58ccf225 100644 --- a/libstdc++-v3/include/std/type_traits +++ b/libstdc++-v3/include/std/type_traits @@ -144,6 +144,11 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION #if __cplusplus >= 201703L + template + inline constexpr bool __or_v = __or_<_Bn...>::value; + template + inline constexpr bool __and_v = __and_<_Bn...>::value; + #define __cpp_lib_logical_traits 201510 template diff --git a/libstdc++-v3/testsuite/20_util/optional/cons/value_neg.cc b/libstdc++-v3/testsuite/20_util/optional/cons/value_neg.cc index e9171ef7cc2..020cb26453f 100644 --- a/libstdc++-v3/testsuite/20_util/optional/cons/value_neg.cc +++ b/libstdc++-v3/testsuite/20_util/optional/cons/value_neg.cc @@ -19,8 +19,6 @@ // . #include -#include - #include #include @@ -37,8 +35,6 @@ int main() std::optional> oup2 = new int; // { dg-error "conversion" } struct U { explicit U(std::in_place_t); }; std::optional ou(std::in_place); // { dg-error "no matching" } - // { dg-error "no type" "" { target { *-*-* } } 1020 } - // { dg-error "no type" "" { target { *-*-* } } 1030 } - // { dg-error "no type" "" { target { *-*-* } } 1087 } } } +// { dg-prune-output "no type .*enable_if" } -- 2.30.2