Abstract-Type and Scheme-Definition Language (ASDL) was a computer language developed as part of ESPRIT project GRASPIN , as a basis for generating language-based editors and environments. It combines an object-oriented type system, syntax-directed translation schemes and a target-language interface .
["ASDL - An Object-Oriented Specification Language for Syntax-Directed Environments", M.L. Christ-Neumann et al, European Software Eng Conf, Strasbourg, Sept 1987, pp.77-85].