xo-expression2: streamline setup

include/xo/expression2/SetupExpression2.hpp

@@ -0,0 +1,25 @@
+/** @file SetupExpression2.hpp
+ *
+ *  @author Roland Conybeare, Jan 2026
+ **/
+
+#pragma once
+
+#include <xo/alloc2/Collector.hpp>
+
+namespace xo {
+    namespace scm {
+        class SetupExpression2 {
+        public:
+            using ACollector = xo::mm::ACollector;
+
+        public:
+            /** Register expression2 (facet,impl) combinations with FacetRegistry **/
+            static bool register_facets();
+            /** Register expression2 (facet,impl) combinations with FacetRegistry **/
+            static bool register_types(obj<ACollector> gc);
+        };
+    }
+}
+
+/* end SetupExpression2.hpp */