xo-facet: + doc scaffold + begin include scaffold

xo-facet/utest/objectmodel.test.cpp

@@ -0,0 +1,61 @@
+/** @file objectmodel.test.cpp
+ *
+ *  @author Roland Conybeare, Dec 2025
+ **/
+
+#include "xo/facet/AFacet.hpp"
+#include <catch2/catch.hpp>
+#include <cmath>
+#include <cassert>
+#include <cstring>
+
+namespace xo {
+    using xo::facet::valid_abstract_facet;
+
+    namespace ut {
+        // ------ AComplex -----
+
+        /** abstract interface for a complex number **/
+        struct AComplex {
+            using TypeErasedIface = struct IComplex_Any;
+
+            virtual double xcoord(void * data) const = 0;
+            virtual double ycoord(void * data) const = 0;
+            virtual double argument(void * data) const = 0;
+            virtual double magnitude(void * data) const = 0;
+
+            virtual void destruct_data(void * data) const = 0;
+
+        private:
+            static bool _valid;
+        };
+
+        bool
+        AComplex::_valid = valid_abstract_facet<AComplex>();
+
+        // ----- IComplex_Any -----
+
+        /** type-erased implementation of AComplex, for runtime polymorphism
+         *  Usable by (and only by) overwriting with a typed implementation,
+         *  such as IComplex_RectCoords or IComplex_PolarCoords.
+         **/
+        struct IComplex_Any : public AComplex {
+            virtual double xcoord(void *) const final override { assert(false); return 0.0; }
+            virtual double ycoord(void *) const final override { assert(false); return 0.0; }
+            virtual double argument(void *) const final override { assert(false); return 0.0; }
+            virtual double magnitude(void *) const final override { assert(false); return 0.0; }
+
+            virtual void destruct_data(void *) const final override { assert(false); }
+
+        private:
+            static bool _valid;
+        };
+
+        bool
+        IComplex_Any::_valid = true; //valid_interface_implementation<AComplex, IComplex_Any>();
+
+
+    }
+}
+
+/* end objectmodel.test.cpp */