Comment by HackerThemAll

Turbo Vision library, which apparently inspired TRust, had a great object model, in which you could derive built-in classes implementing controls, windows, validators etc., extend them by adding custom functionalities and seamlessly plug them into the system. Imagine extending the built-in TEditor class to handle syntax highlighting, or extending TDialog to handle complex multi-tab option dialogs.

To beat 1989 and Turbo Pascal, TRust must do that (perhaps the Rust's way).