xo-alloc2: DX1CollectorIterator infra [WIP]

src/alloc2/IAllocIterator_DArenaIterator.cpp

@@ -0,0 +1,43 @@
+/** @file IAllocIterator_DArenaIterator.cpp
+ *
+ *  @author Roland Conybeare, Dec 2025
+ **/
+
+#include "arena/IAllocIterator_DArenaIterator.hpp"
+#include "AllocIterator.hpp"
+#include <cassert>
+
+namespace xo {
+    using std::byte;
+
+    namespace mm {
+        AllocInfo
+        IAllocIterator_DArenaIterator::deref(const DArenaIterator & ix) noexcept
+        {
+            return ix.deref();
+        }
+
+        cmpresult
+        IAllocIterator_DArenaIterator::compare(const DArenaIterator & ix,
+                                               const obj<AAllocIterator> & other_arg) noexcept
+        {
+            /* downcast from variant */
+            auto other = obj<AAllocIterator, DArenaIterator>::from(other_arg);
+
+            if (!other)
+                return cmpresult::incomparable();
+
+            DArenaIterator & other_ix = *other;
+
+            return ix.compare(other_ix);
+        }
+
+        void
+        IAllocIterator_DArenaIterator::next(DArenaIterator & ix) noexcept
+        {
+            ix.next();
+        }
+    } /*namespace mm*/
+} /*namespace xo*/
+
+/* end IAllocIterator_DArenaIterator.cpp */