DEUCE : A Declarative Framework for Extricating User Interface Concerns

Evolving a software system not only affects the source code responsible for the core application, but also the user interface. Unfortunately user interface code is often scattered through and entangled with the application code. In large and complex user-interfaces, this tangling renders the implementation complex and hard to maintain. Currently, the application needs to perform both the necessary changes to the user-interface (e.g. disabling other buttons, propagating events, etc.) as well as invoke the required application logic. The Deuce framework (Declarative User Interface Concerns Extrication) intends to reduce the complexity of user-interface implementations by applying separation of concerns on three UI concerns : presentation logic, business and data logic, and connection logic. It does so by using a declarative meta-language (SOUL) on top of an object oriented language (Smalltalk) such that an adequate language is provided to describe the entire structure and behaviour of the user-interface, as well as to link it with the application.