mirror of
https://github.com/AntelopeIO/cdt-libcxx.git
synced 2026-07-21 13:53:36 +00:00
Eric Fiselier
35ce4859dd
Summary: Adapt implementation of Library Fundamentals TS optional into an implementation of N4606 optional. - Update relational operators per http://wg21.link/P0307 - Update to requirements of http://wg21.link/P0032 - Extension: Implement trivial copy/move construction/assignment for `optional<T>` when `T` is trivially copyable. Audit P/Rs for optional LWG issues: - 2756 "C++ WP optional<T> should 'forward' T's implicit conversions" Implemented, which also resolves 2753 "Optional's constructors and assignments need constraints" (modulo my refusal to explicitly delete the move operations, which is a design error that I'm working on correcting in the 2756 P/R). - 2736 "nullopt_t insufficiently constrained" Already conforming. I've added a test ensuring that `nullopt_t` is not copy-initializable from an empty braced-init-list, which I believe is the root intent of the issue, to avoid regression. - 2740 "constexpr optional<T>::operator->" Already conforming. - 2746 "Inconsistency between requirements for emplace between optional and variant" No P/R, but note that the author's '"suggested resolution" is already implemented. - 2748 "swappable traits for optionals" Already conforming. - 2753 "Optional's constructors and assignments need constraints" Implemented. Most of the work for this patch was done by Casey Carter @ Microsoft. Thank you Casey! Reviewers: mclow.lists, CaseyCarter, EricWF Differential Revision: https://reviews.llvm.org/D22741 git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@283980 91177308-0d34-0410-b5e6-96231b3b80d8
67 lines
2.2 KiB
C++
67 lines
2.2 KiB
C++
//===----------------------------------------------------------------------===//
|
|
//
|
|
// The LLVM Compiler Infrastructure
|
|
//
|
|
// This file is dual licensed under the MIT and the University of Illinois Open
|
|
// Source Licenses. See LICENSE.TXT for details.
|
|
//
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
// UNSUPPORTED: c++98, c++03, c++11, c++14
|
|
// <optional>
|
|
|
|
|
|
#include <optional>
|
|
#include <type_traits>
|
|
#include <cassert>
|
|
|
|
#include "archetypes.hpp"
|
|
|
|
template <class T>
|
|
struct SpecialMemberTest {
|
|
using O = std::optional<T>;
|
|
|
|
template <template <class> class TestMF>
|
|
static constexpr bool check_same() {
|
|
return TestMF<O>::value == TestMF<T>::value;
|
|
}
|
|
|
|
// Test that optional inherits the correct trivial/non-trivial members
|
|
static_assert(check_same<std::is_trivially_destructible>(), "");
|
|
static_assert(check_same<std::is_trivially_copyable>(), "");
|
|
};
|
|
|
|
template <class ...Args> static void sink(Args&&...) {}
|
|
|
|
template <class ...TestTypes>
|
|
struct DoTestsMetafunction {
|
|
DoTestsMetafunction() { sink(SpecialMemberTest<TestTypes>{}...); }
|
|
};
|
|
|
|
struct TrivialMoveNonTrivialCopy {
|
|
TrivialMoveNonTrivialCopy() = default;
|
|
TrivialMoveNonTrivialCopy(const TrivialMoveNonTrivialCopy&) {}
|
|
TrivialMoveNonTrivialCopy(TrivialMoveNonTrivialCopy&&) = default;
|
|
TrivialMoveNonTrivialCopy& operator=(const TrivialMoveNonTrivialCopy&) { return *this; }
|
|
TrivialMoveNonTrivialCopy& operator=(TrivialMoveNonTrivialCopy&&) = default;
|
|
};
|
|
|
|
struct TrivialCopyNonTrivialMove {
|
|
TrivialCopyNonTrivialMove() = default;
|
|
TrivialCopyNonTrivialMove(const TrivialCopyNonTrivialMove&) = default;
|
|
TrivialCopyNonTrivialMove(TrivialCopyNonTrivialMove&&) {}
|
|
TrivialCopyNonTrivialMove& operator=(const TrivialCopyNonTrivialMove&) = default;
|
|
TrivialCopyNonTrivialMove& operator=(TrivialCopyNonTrivialMove&&) { return *this; }
|
|
};
|
|
|
|
int main()
|
|
{
|
|
sink(
|
|
ImplicitTypes::ApplyTypes<DoTestsMetafunction>{},
|
|
ExplicitTypes::ApplyTypes<DoTestsMetafunction>{},
|
|
NonLiteralTypes::ApplyTypes<DoTestsMetafunction>{},
|
|
NonTrivialTypes::ApplyTypes<DoTestsMetafunction>{},
|
|
DoTestsMetafunction<TrivialMoveNonTrivialCopy, TrivialCopyNonTrivialMove>{}
|
|
);
|
|
}
|