Recommit r276548 - Make pair/tuples assignment operators SFINAE properly.
I think I've solved issues with is_assignable and references to incomplete
types. The updated patch adds tests for this case.
llvm-svn: 276603
diff --git a/libcxx/include/utility b/libcxx/include/utility
index 022a641..456a5f7 100644
--- a/libcxx/include/utility
+++ b/libcxx/include/utility
@@ -348,8 +348,23 @@
// Use the implicitly declared copy constructor in C++03
#endif
+#if !defined(_LIBCPP_CXX03_LANG)
+ typedef typename conditional<
+ is_copy_assignable<_T1>::value
+ && is_copy_assignable<_T2>::value,
+ pair, __nat
+ >::type _CopyAssignT;
+ typedef typename conditional<
+ is_move_assignable<_T1>::value
+ && is_move_assignable<_T2>::value,
+ pair, __nat
+ >::type _MoveAssignT;
+#else
+ typedef pair _CopyAssignT;
+#endif
+
_LIBCPP_INLINE_VISIBILITY
- pair& operator=(const pair& __p)
+ pair& operator=(_CopyAssignT const& __p)
_NOEXCEPT_(is_nothrow_copy_assignable<first_type>::value &&
is_nothrow_copy_assignable<second_type>::value)
{
@@ -358,6 +373,18 @@
return *this;
}
+#ifndef _LIBCPP_CXX03_LANG
+ _LIBCPP_INLINE_VISIBILITY
+ pair& operator=(_MoveAssignT&& __p)
+ _NOEXCEPT_(is_nothrow_move_assignable<first_type>::value &&
+ is_nothrow_move_assignable<second_type>::value)
+ {
+ first = _VSTD::forward<first_type>(__p.first);
+ second = _VSTD::forward<second_type>(__p.second);
+ return *this;
+ }
+#endif
+
#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
template <class _U1, class _U2,
@@ -377,18 +404,9 @@
: first(_VSTD::forward<_U1>(__p.first)),
second(_VSTD::forward<_U2>(__p.second)) {}
- _LIBCPP_INLINE_VISIBILITY
- pair&
- operator=(pair&& __p) _NOEXCEPT_(is_nothrow_move_assignable<first_type>::value &&
- is_nothrow_move_assignable<second_type>::value)
- {
- first = _VSTD::forward<first_type>(__p.first);
- second = _VSTD::forward<second_type>(__p.second);
- return *this;
- }
+
#ifndef _LIBCPP_HAS_NO_VARIADICS
-
template<class _Tuple,
class = typename enable_if<__tuple_convertible<_Tuple, pair>::value>::type>
_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
@@ -411,7 +429,7 @@
{}
template <class _Tuple,
- class = typename enable_if<__tuple_assignable<_Tuple, pair>::value>::type>
+ class = typename enable_if<!is_same<typename decay<_Tuple>::type, pair>::value && __tuple_assignable<_Tuple, pair>::value>::type>
_LIBCPP_INLINE_VISIBILITY
pair&
operator=(_Tuple&& __p)