The authors present the Abstract-Type and Scheme-Definition Language (ASDL), a new formalism and environment kernel. The main goal of this object-oriented kernel is to reconcile integration and extensibility. ASDL adopts the ideas underlying language-based editor generators but overcomes their extensibility deficiencies. ASDL combines an object-oriented type system with syntax-directed translation schemes and a target-language interface. Its power lies in utilizing inheritance for structure-driven computations. The authors discuss object types, translation rules, and semantic information in ASDL.
