Implement N4606 optional
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
llvm-svn: 283980
Cr-Mirrored-From: sso://chromium.googlesource.com/_direct/external/github.com/llvm/llvm-project
Cr-Mirrored-Commit: a9e659619f592c49b352af16253ec0b79c207956
diff --git a/src/optional.cpp b/src/optional.cpp
index 8c5dd76..f2fbfdf 100644
--- a/src/optional.cpp
+++ b/src/optional.cpp
@@ -7,18 +7,18 @@
//
//===----------------------------------------------------------------------===//
+#include "optional"
#include "experimental/optional"
-_LIBCPP_BEGIN_NAMESPACE_EXPERIMENTAL
-
-#ifdef _LIBCPP_HAS_NO_DEFAULTED_FUNCTIONS
-
-bad_optional_access::~bad_optional_access() _NOEXCEPT {}
-
-#else
+namespace std
+{
bad_optional_access::~bad_optional_access() _NOEXCEPT = default;
-#endif
+} // std
+
+_LIBCPP_BEGIN_NAMESPACE_EXPERIMENTAL
+
+bad_optional_access::~bad_optional_access() _NOEXCEPT = default;
_LIBCPP_END_NAMESPACE_EXPERIMENTAL