Integrations (PTC products, 3rd party products and code) > Code integration (Ada, ARINC 653, C, C#, C++, IDL, Java, SQL and VB) > Transformation Development Kit (TDK) > Customizing an ACS Code Generator DLL > Customizing a TDK code generation transformation patterns model - current TDK models > Changing code generation definition in a TDK code generation transformation patterns model > Declaring extended properties in a TDK code generation transformation patterns model
  
Declaring extended properties in a TDK code generation transformation patterns model
If you want the generated ACS Code Generator DLL to work with extended properties of a Modeler item type that you have created or that are not being worked with at present, you must declare those extended properties on the appropriate Meta Class through inheritance.
For more information about declaring extended properties, see Declaration of Modeler item types and extended properties - 4G meta classes (TDK).
* 
Do not create new Attributes on the provided Meta Classes - if you do so, your changes will be lost should you update the TDK Code Generation Transformation Patterns model with improvements provided in a future release of Modeler.
To declare new extended properties:
1. Before declaring a new extended property for a Modeler item type, check that the Meta Class for that item type does not declare that extended property already.
The provided Meta Types reside in the Generator::Structure package.
2. Create a new Package in the TDK model that is not scoped to the Generator or TDK Generator Framework packages.
3. In the Package you created, create a Class Diagram to show your Meta Class extensions.
4. On the Class Diagram you created, create a Class, and name the Class appropriately.
For example, if the Class is going to extend the Operation meta class, set the name of the Class to Operation Extensions.
5. On the Class you created, create an Attribute.
6. Set the name of the Attribute to that of the extended property you want to declare.
7. Add to the Class Diagram you created, the Meta Class you are extending.
8. On the Class Diagram toolbar, click the Abstraction button, click the provided Meta Class, and then click the Class you created.
9. Apply the 4GExtends stereotype to the Dependency you created. How?