Massive simplification of boxed_cast. More planned

include/chaiscript/dispatchkit/boxed_cast.hpp

@@ -69,7 +69,7 @@ namespace chaiscript
   /// assert(i == 5);
   /// \endcode
   template<typename Type>
-  typename detail::Cast_Helper<Type>::Result_Type boxed_cast(const Boxed_Value &bv, const Type_Conversions_State *t_conversions = nullptr)
+  auto boxed_cast(const Boxed_Value &bv, const Type_Conversions_State *t_conversions = nullptr) -> decltype(detail::Cast_Helper<Type>::cast(bv, nullptr))
   {
     if (!t_conversions || bv.get_type_info().bare_equal(user_type<Type>()) || (t_conversions && !(*t_conversions)->convertable_type<Type>())) {
       try {

include/chaiscript/dispatchkit/boxed_cast_helper.hpp

@@ -29,21 +29,36 @@ namespace chaiscript
         throw std::runtime_error("Attempted to dereference null Boxed_Value");
       }
 
+    const void *verify_type(const Boxed_Value &ob, const std::type_info &ti, const void *ptr) {
+      if (!ob.get_type_info().bare_equal_type_info(ti)) {
+        throw chaiscript::detail::exception::bad_any_cast();
+      } else {
+        return throw_if_null(ptr);
+      }
+    }
+
+    void *verify_type(const Boxed_Value &ob, const std::type_info &ti, void *ptr) {
+      if (ptr == nullptr || !ob.get_type_info().bare_equal_type_info(ti)) {
+        throw chaiscript::detail::exception::bad_any_cast();
+      } else {
+        return ptr;
+      }
+    }
+
+    /*
+    template<typename Result, typename = enable_if<Result>>
+      Result cast_helper_inner(const Boxed_Value &ob, const Type_Conversions_State *)
+      {
+      }
+*/
+
     /// Generic Cast_Helper_Inner, for casting to any type
     template<typename Result>
       struct Cast_Helper_Inner
       {
-        typedef typename std::add_const<Result>::type Result_Type;
+        static Result cast(const Boxed_Value &ob, const Type_Conversions_State *)
-
-        static Result_Type cast(const Boxed_Value &ob, const Type_Conversions_State *)
         {
-          if (ob.get_type_info().bare_equal_type_info(typeid(Result)))
+          return *static_cast<const Result *>(verify_type(ob, typeid(Result), ob.get_const_ptr()));
-          {
-            auto p = throw_if_null(ob.get_const_ptr());
-            return *static_cast<const Result *>(p);
-          } else {
-            throw chaiscript::detail::exception::bad_any_cast();
-          }
         }
       };
 
@@ -57,15 +72,9 @@ namespace chaiscript
     template<typename Result>
       struct Cast_Helper_Inner<const Result *>
       {
-        typedef const Result * Result_Type;
+        static auto cast(const Boxed_Value &ob, const Type_Conversions_State *)
-        static Result_Type cast(const Boxed_Value &ob, const Type_Conversions_State *)
         {
-          if (ob.get_type_info().bare_equal_type_info(typeid(Result)))
+          return static_cast<const Result *>(verify_type(ob, typeid(Result), ob.get_const_ptr()));
-          {
-            return static_cast<const Result *>(ob.get_const_ptr());
-          } else {
-            throw chaiscript::detail::exception::bad_any_cast();
-          }
         }
       };
 
@@ -73,15 +82,9 @@ namespace chaiscript
     template<typename Result>
       struct Cast_Helper_Inner<Result *>
       {
-        typedef Result * Result_Type;
+        static auto cast(const Boxed_Value &ob, const Type_Conversions_State *)
-        static Result_Type cast(const Boxed_Value &ob, const Type_Conversions_State *)
         {
-          if (!ob.get_type_info().is_const() && ob.get_type_info() == typeid(Result))
+          return static_cast<Result *>(verify_type(ob, typeid(Result), ob.get_ptr()));
-          {
-            return static_cast<Result *>(ob.get_ptr());
-          } else {
-            throw chaiscript::detail::exception::bad_any_cast();
-          }
         }
       };
 
@@ -100,17 +103,9 @@ namespace chaiscript
     template<typename Result>
       struct Cast_Helper_Inner<const Result &>
       {
-        typedef const Result& Result_Type;
+        static const Result & cast(const Boxed_Value &ob, const Type_Conversions_State *)
-
-        static Result_Type cast(const Boxed_Value &ob, const Type_Conversions_State *)
         {
-          if (ob.get_type_info().bare_equal_type_info(typeid(Result)))
+          return *static_cast<const Result *>(verify_type(ob, typeid(Result), ob.get_const_ptr()));
-          {
-            auto p = throw_if_null(ob.get_const_ptr());
-            return *static_cast<const Result *>(p);
-          } else {
-            throw chaiscript::detail::exception::bad_any_cast();
-          }
         }
       };
 
@@ -120,16 +115,9 @@ namespace chaiscript
     template<typename Result>
       struct Cast_Helper_Inner<Result &>
       {
-        typedef Result& Result_Type;
+        static Result& cast(const Boxed_Value &ob, const Type_Conversions_State *)
-
-        static Result_Type cast(const Boxed_Value &ob, const Type_Conversions_State *)
         {
-          if (!ob.get_type_info().is_const() && ob.get_type_info().bare_equal_type_info(typeid(Result)))
+          return *static_cast<Result *>(verify_type(ob, typeid(Result), ob.get_ptr()));
-          {
-            return *(static_cast<Result *>(throw_if_null(ob.get_ptr())));
-          } else {
-            throw chaiscript::detail::exception::bad_any_cast();
-          }
         }
       };
 
@@ -137,9 +125,7 @@ namespace chaiscript
     template<typename Result>
       struct Cast_Helper_Inner<std::shared_ptr<Result> >
       {
-        typedef std::shared_ptr<Result> Result_Type;
+        static auto cast(const Boxed_Value &ob, const Type_Conversions_State *)
-
-        static Result_Type cast(const Boxed_Value &ob, const Type_Conversions_State *)
         {
           return ob.get().cast<std::shared_ptr<Result> >();
         }
@@ -149,9 +135,7 @@ namespace chaiscript
     template<typename Result>
       struct Cast_Helper_Inner<std::shared_ptr<const Result> >
       {
-        typedef std::shared_ptr<const Result> Result_Type;
+        static auto cast(const Boxed_Value &ob, const Type_Conversions_State *)
-
-        static Result_Type cast(const Boxed_Value &ob, const Type_Conversions_State *)
         {
           if (!ob.get_type_info().is_const())
           {
@@ -177,10 +161,7 @@ namespace chaiscript
       struct Cast_Helper_Inner<std::shared_ptr<Result> &>
       {
         static_assert(!std::is_const<Result>::value, "Non-const reference to std::shared_ptr<const T> is not supported");
-
+        static auto cast(const Boxed_Value &ob, const Type_Conversions_State *)
-        typedef Boxed_Value::Sentinel<Result> Result_Type;
-
-        static Result_Type cast(const Boxed_Value &ob, const Type_Conversions_State *)
         {
           std::shared_ptr<Result> &res = ob.get().cast<std::shared_ptr<Result> >();
           return ob.pointer_sentinel(res);
@@ -204,9 +185,7 @@ namespace chaiscript
     template<>
       struct Cast_Helper_Inner<Boxed_Value>
       {
-        typedef Boxed_Value Result_Type;
+        static Boxed_Value cast(const Boxed_Value &ob, const Type_Conversions_State *)
-
-        static Result_Type cast(const Boxed_Value &ob, const Type_Conversions_State *)
         {
           return ob;
         }
@@ -216,9 +195,7 @@ namespace chaiscript
     template<>
       struct Cast_Helper_Inner<Boxed_Value &>
       {
-        typedef std::reference_wrapper<Boxed_Value> Result_Type;
+        static std::reference_wrapper<Boxed_Value> cast(const Boxed_Value &ob, const Type_Conversions_State *)
-
-        static Result_Type cast(const Boxed_Value &ob, const Type_Conversions_State *)
         {
           return std::ref(const_cast<Boxed_Value &>(ob));
         }
@@ -272,9 +249,7 @@ namespace chaiscript
     template<typename T>
       struct Cast_Helper
       {
-        typedef typename Cast_Helper_Inner<T>::Result_Type Result_Type;
+        static auto cast(const Boxed_Value &ob, const Type_Conversions_State *t_conversions) -> decltype(Cast_Helper_Inner<T>::cast(ob, t_conversions))
-
-        static Result_Type cast(const Boxed_Value &ob, const Type_Conversions_State *t_conversions)
         {
           return Cast_Helper_Inner<T>::cast(ob, t_conversions);
         }

include/chaiscript/dispatchkit/boxed_number.hpp

@@ -1009,9 +1009,7 @@ namespace chaiscript
     template<>
       struct Cast_Helper<Boxed_Number>
       {
-        typedef Boxed_Number Result_Type;
+        static Boxed_Number cast(const Boxed_Value &ob, const Type_Conversions_State *)
-
-        static Result_Type cast(const Boxed_Value &ob, const Type_Conversions_State *)
         {
           return Boxed_Number(ob);
         }

include/chaiscript/dispatchkit/dispatchkit.hpp

@@ -424,7 +424,7 @@ namespace chaiscript
 
         /// \brief casts an object while applying any Dynamic_Conversion available
         template<typename Type>
-          typename detail::Cast_Helper<Type>::Result_Type boxed_cast(const Boxed_Value &bv) const
+          auto boxed_cast(const Boxed_Value &bv) const -> decltype(chaiscript::boxed_cast<Type>(bv, nullptr)) 
           {
             Type_Conversions_State state(m_conversions, m_conversions.conversion_saves());
             return chaiscript::boxed_cast<Type>(bv, &state);

include/chaiscript/dispatchkit/function_call.hpp

@@ -81,9 +81,7 @@ namespace chaiscript
     template<typename Signature>
       struct Cast_Helper<const std::function<Signature> &>
       {
-        typedef std::function<Signature> Result_Type;
+        static std::function<Signature> cast(const Boxed_Value &ob, const Type_Conversions_State *t_conversions)
-
-        static Result_Type cast(const Boxed_Value &ob, const Type_Conversions_State *t_conversions)
         {
           if (ob.get_type_info().bare_equal(user_type<Const_Proxy_Function>()))
           {
@@ -98,9 +96,7 @@ namespace chaiscript
     template<typename Signature>
       struct Cast_Helper<std::function<Signature> >
       {
-        typedef std::function<Signature> Result_Type;
+        static std::function<Signature> cast(const Boxed_Value &ob, const Type_Conversions_State *t_conversions)
-
-        static Result_Type cast(const Boxed_Value &ob, const Type_Conversions_State *t_conversions)
         {
           if (ob.get_type_info().bare_equal(user_type<Const_Proxy_Function>()))
           {
@@ -115,9 +111,7 @@ namespace chaiscript
     template<typename Signature>
       struct Cast_Helper<const std::function<Signature> >
       {
-        typedef std::function<Signature> Result_Type;
+        static std::function<Signature> cast(const Boxed_Value &ob, const Type_Conversions_State *t_conversions)
-
-        static Result_Type cast(const Boxed_Value &ob, const Type_Conversions_State *t_conversions)
         {
           if (ob.get_type_info().bare_equal(user_type<Const_Proxy_Function>()))
           {

include/chaiscript/language/chaiscript_engine.hpp

@@ -690,7 +690,7 @@ namespace chaiscript
 
     /// \brief casts an object while applying any Dynamic_Conversion available
     template<typename Type>
-      typename detail::Cast_Helper<Type>::Result_Type boxed_cast(const Boxed_Value &bv) const
+      auto boxed_cast(const Boxed_Value &bv) const -> decltype(m_engine.boxed_cast<Type>(bv))
       {
         return m_engine.boxed_cast<Type>(bv);
       }