internal static IntPtr CreateSubType(IntPtr py_name, IntPtr py_base_type, IntPtr py_dict) { var dictRef = new BorrowedReference(py_dict); // Utility to create a subtype of a managed type with the ability for the // a python subtype able to override the managed implementation string name = Runtime.GetManagedString(py_name); // the derived class can have class attributes __assembly__ and __module__ which // control the name of the assembly and module the new type is created in. object assembly = null; object namespaceStr = null; using (var assemblyKey = new PyString("__assembly__")) { var assemblyPtr = Runtime.PyDict_GetItemWithError(dictRef, assemblyKey.Reference); if (assemblyPtr.IsNull) { if (Exceptions.ErrorOccurred()) { return(IntPtr.Zero); } } else if (!Converter.ToManagedValue(assemblyPtr, typeof(string), out assembly, true)) { return(Exceptions.RaiseTypeError("Couldn't convert __assembly__ value to string")); } using (var namespaceKey = new PyString("__namespace__")) { var pyNamespace = Runtime.PyDict_GetItemWithError(dictRef, namespaceKey.Reference); if (pyNamespace.IsNull) { if (Exceptions.ErrorOccurred()) { return(IntPtr.Zero); } } else if (!Converter.ToManagedValue(pyNamespace, typeof(string), out namespaceStr, true)) { return(Exceptions.RaiseTypeError("Couldn't convert __namespace__ value to string")); } } } // create the new managed type subclassing the base managed type var baseClass = ManagedType.GetManagedObject(py_base_type) as ClassBase; if (null == baseClass) { return(Exceptions.RaiseTypeError("invalid base class, expected CLR class type")); } try { Type subType = ClassDerivedObject.CreateDerivedType(name, baseClass.type.Value, py_dict, (string)namespaceStr, (string)assembly); // create the new ManagedType and python type ClassBase subClass = ClassManager.GetClass(subType); IntPtr py_type = GetTypeHandle(subClass, subType); // by default the class dict will have all the C# methods in it, but as this is a // derived class we want the python overrides in there instead if they exist. var cls_dict = new BorrowedReference(Marshal.ReadIntPtr(py_type, TypeOffset.tp_dict)); ThrowIfIsNotZero(Runtime.PyDict_Update(cls_dict, new BorrowedReference(py_dict))); Runtime.XIncref(py_type); // Update the __classcell__ if it exists BorrowedReference cell = Runtime.PyDict_GetItemString(cls_dict, "__classcell__"); if (!cell.IsNull) { ThrowIfIsNotZero(Runtime.PyCell_Set(cell, py_type)); ThrowIfIsNotZero(Runtime.PyDict_DelItemString(cls_dict, "__classcell__")); } return(py_type); } catch (Exception e) { return(Exceptions.RaiseTypeError(e.Message)); } }