From aa55e20e1279800980bba44e736c2a4af0cc560a Mon Sep 17 00:00:00 2001
From: Roland Conybeare <rconybeare@gmail.com>
Date: Fri, 14 Jun 2024 10:55:08 -0400
Subject: [PATCH] xo-reflect: + infra for reflecting functions

---
 include/xo/reflect/Metatype.hpp             | 57 +++++++++++----------
 include/xo/reflect/function/FunctionTdx.hpp | 49 ++++++++++++++++++
 src/reflect/function/FunctionTdx.cpp        | 37 +++++++++++++
 3 files changed, 116 insertions(+), 27 deletions(-)
 create mode 100644 include/xo/reflect/function/FunctionTdx.hpp
 create mode 100644 src/reflect/function/FunctionTdx.cpp

diff --git a/include/xo/reflect/Metatype.hpp b/include/xo/reflect/Metatype.hpp
index 23f3fd10..549d098e 100644
--- a/include/xo/reflect/Metatype.hpp
+++ b/include/xo/reflect/Metatype.hpp
@@ -5,34 +5,37 @@
 #include <iostream>
 
 namespace xo {
-  namespace reflect {
-    enum class Metatype { mt_invalid, mt_atomic, mt_pointer, mt_vector, mt_struct };
+    namespace reflect {
+        enum class Metatype { mt_invalid, mt_atomic, mt_pointer, mt_vector, mt_struct, mt_function };
 
-    inline std::ostream & operator<<(std::ostream & os,
-				     Metatype x) {
-      switch(x) {
-      case Metatype::mt_invalid:
-	os << "invalid!";
-	break;
-      case Metatype::mt_atomic:
-	os << "atomic";
-	break;
-      case Metatype::mt_pointer:
-	os << "pointer";
-	break;
-      case Metatype::mt_vector:
-	os << "vector";
-	break;
-      case Metatype::mt_struct:
-	os << "struct";
-	break;
-      default:
-	os << "???";
-      }
-      return os;
-    } /*operator<<*/
-      
-  } /*namespace reflect*/
+        inline std::ostream & operator<<(std::ostream & os,
+                                         Metatype x) {
+            switch(x) {
+            case Metatype::mt_invalid:
+                os << "invalid!";
+                break;
+            case Metatype::mt_atomic:
+                os << "atomic";
+                break;
+            case Metatype::mt_pointer:
+                os << "pointer";
+                break;
+            case Metatype::mt_vector:
+                os << "vector";
+                break;
+            case Metatype::mt_struct:
+                os << "struct";
+                break;
+            case Metatype::mt_function:
+                os << "function";
+                break;
+            default:
+                os << "???";
+            }
+            return os;
+        } /*operator<<*/
+
+    } /*namespace reflect*/
 } /*namespace xo*/
 
 /* end Metatype.hpp */
diff --git a/include/xo/reflect/function/FunctionTdx.hpp b/include/xo/reflect/function/FunctionTdx.hpp
new file mode 100644
index 00000000..1558328d
--- /dev/null
+++ b/include/xo/reflect/function/FunctionTdx.hpp
@@ -0,0 +1,49 @@
+/** @file FunctionTdx.hpp
+ *
+ *  Author: Roland Conybeare
+ **/
+
+#pragma once
+
+#include "xo/reflect/TypeDescrExtra.hpp"
+#include "xo/reflect/EstablishTypeDescr.hpp"
+
+namespace xo {
+    namespace reflect {
+        /** Additional type-associated information for a function/procedure **/
+        class FunctionTdx : public TypeDescrExtra {
+        public:
+            virtual ~FunctionTdx() = default;
+
+            /** create instance.  Will be invoked exactly once for each reflected function type **/
+            static std::unique_ptr<FunctionTdx> make_function(TypeDescr retval_td,
+                                                              std::vector<TypeDescr> arg_td_v);
+
+
+
+            // ----- Inherited from TypeDescrExtra -----
+
+            virtual Metatype metatype() const override { return Metatype::mt_function; }
+            virtual uint32_t n_child(void * /*object*/) const override { return 0; }
+            virtual TaggedPtr child_tp(uint32_t i, void * object) const override;
+            const std::string & struct_member_name(uint32_t i) const override;
+
+            virtual uint32_t n_fn_arg() const override { return arg_td_v_.size(); }
+            virtual TypeDescr fn_retval() const override { return retval_td_; }
+            virtual TypeDescr fn_arg(uint32_t i) const override { return arg_td_v_[i]; }
+
+        private:
+            FunctionTdx(TypeDescr retval_td,
+                        std::vector<TypeDescr> arg_td_v);
+
+        private:
+            /** function return value **/
+            TypeDescr retval_td_;
+            /** function arguments,  in positional order **/
+            std::vector<TypeDescr> arg_td_v_;
+        }; /*FunctionTdx*/
+    } /*namespace reflect*/
+} /*namespace xo*/
+
+
+/** end FunctionTdx.hpp **/
diff --git a/src/reflect/function/FunctionTdx.cpp b/src/reflect/function/FunctionTdx.cpp
new file mode 100644
index 00000000..1b715fcd
--- /dev/null
+++ b/src/reflect/function/FunctionTdx.cpp
@@ -0,0 +1,37 @@
+/* @file FunctionTdx.cpp */
+
+#include "function/FunctionTdx.hpp"
+#include "TaggedPtr.hpp"
+
+namespace xo {
+    namespace reflect {
+            /** create instance.  Will be invoked exactly once for each reflected function type **/
+        std::unique_ptr<FunctionTdx>
+        FunctionTdx::make_function(TypeDescr retval_td,
+                                   std::vector<TypeDescr> arg_td_v)
+        {
+            return std::unique_ptr<FunctionTdx>(new FunctionTdx(retval_td, std::move(arg_td_v)));
+        }
+
+        FunctionTdx::FunctionTdx(TypeDescr retval_td,
+                                 std::vector<TypeDescr> arg_td_v)
+            : retval_td_{retval_td},
+              arg_td_v_{std::move(arg_td_v)}
+        {}
+
+        TaggedPtr
+        FunctionTdx::child_tp(uint32_t /*i*/, void * /*object*/) const
+        {
+            return TaggedPtr::universal_null();
+        }
+
+        const std::string &
+        FunctionTdx::struct_member_name(uint32_t i) const
+        {
+            return TypeDescrExtra::struct_member_name(i);
+        }
+    } /*namespace reflect*/
+} /*namespace xo*/
+
+
+/* end FunctionTdx.cpp */