[libcxx-commits] [libcxx] [libc++] Remove `optional::iterator` from experimental mode (PR #203782)

[Louis Dionne via libcxx-commits]

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@@ -681,50 +682,77 @@ class _LIBCPP_DECLSPEC_EMPTY_BASES optional
 
   using __base::reset;
 
-#  if _LIBCPP_STD_VER >= 26 && _LIBCPP_HAS_EXPERIMENTAL_OPTIONAL_ITERATOR
+#  if _LIBCPP_STD_VER >= 26
 
 private:
   using __pointer _LIBCPP_NODEBUG       = add_pointer_t<_Tp>;
   using __const_pointer _LIBCPP_NODEBUG = add_pointer_t<const _Tp>;
 
-public:
+  template <class _Up = _Tp, bool = std::__range_fits_in_alignment(alignof(_Up), 1)>
+  struct __iterator {
 #    ifdef _LIBCPP_ABI_BOUNDED_ITERATORS_IN_OPTIONAL
-  using iterator       = __bounded_iter<__pointer>;
-  using const_iterator = __bounded_iter<__const_pointer>;
+    using __type _LIBCPP_NODEBUG       = std::__bounded_iter<__pointer>;
+    using __const_type _LIBCPP_NODEBUG = std::__bounded_iter<__const_pointer>;
 #    else
-  using iterator       = __capacity_aware_iterator<__pointer, 1>;
-  using const_iterator = __capacity_aware_iterator<__const_pointer, 1>;
+    using __type _LIBCPP_NODEBUG       = std::__static_packed_bounded_iterator<__pointer, 1>;
+    using __const_type _LIBCPP_NODEBUG = std::__static_packed_bounded_iterator<__const_pointer, 1>;
 #    endif
 
-  // [optional.iterators], iterator support
-  [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr iterator begin() noexcept {
-    auto* __ptr = std::addressof(this->__val_);
-
+    template <class _PtrType>
+    static auto __make(_PtrType __p, [[__maybe_unused__]] unsigned __end_offset) noexcept {
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ldionne wrote:

Suggestion to pass `true|false /* is engaged */` instead and to compute the offset inside `__make` -- that way the rest of the code doesn't have to reason about how the iterator interacts with offsets.

https://github.com/llvm/llvm-project/pull/203782