feat(DaedalusVm): allow default externals to take a DaedalusSymbol …

…reference

include/zenkit/DaedalusVm.hh

@@ -605,9 +605,20 @@ namespace zenkit {
 		/// underflows.
 		///
 		/// \param callback The function to call. The one parameter of the function is the name of the unresolved
-		/// external.
+		///                 external.
 		ZKAPI void register_default_external(std::function<void(std::string_view)> const& callback);
 
+		/// \brief Registers a function to be called when the script tries to call an external which has not been
+		///        registered.
+		///
+		/// Before the callback is invoked, the VM makes sure that all parameters for the external are popped off
+		/// the stack and a default return value (if needed) is pushed onto the stack. This prevents stack
+		/// underflows.
+		///
+		/// \param callback The function to call. The one parameter of the function is the symbol of the unresolved
+		///                 external.
+		ZKAPI void register_default_external(std::function<void(DaedalusSymbol const&)> const& callback);
+
 		ZKAPI void register_default_external_custom(std::function<void(DaedalusVm&, DaedalusSymbol&)> const& callback);
 
 		ZKAPI void register_access_trap(std::function<void(DaedalusSymbol&)> const& callback);

src/DaedalusVm.cc

@@ -600,6 +600,10 @@ namespace zenkit {
 	}
 
 	void DaedalusVm::register_default_external(std::function<void(std::string_view)> const& callback) {
+		this->register_default_external([&callback](DaedalusSymbol const& sym) { callback(sym.name()); });
+	}
+
+	void DaedalusVm::register_default_external(std::function<void(DaedalusSymbol const&)> const& callback) {
 		_m_default_external = [this, callback](DaedalusVm& v, DaedalusSymbol const& sym) {
 			// pop all parameters from the stack
 			auto params = find_parameters_for_function(&sym);
@@ -624,7 +628,7 @@ namespace zenkit {
 					v.push_instance(nullptr);
 			}
 
-			callback(sym.name());
+			callback(sym);
 		};
 	}