9701826 A four-year program of research and education is proposed, covering a range of topics connected by a common concern with OBJECTS and concentrating in two major areas: (1) development of STATIC TYPE SYSTEMS for object-oriented languages and (2) study of CONCURRENT and DISTRIBUTED OBJECTS. Specific goals include: comparison and consolidation of different type-theoretic models of objects; investigation of the key mechanism of "polymorphic update" of structured data; development of useful partial type reconstruction techniques for languages with subtyping and polymorphism; investigation of the role of parametric polymorphism in modular reasoning about concurrent systems; and the study of type systems capable of ensuring various forms of noninterference between concurrent activities. An important research vehicle is the experimental programming language Pict, a testbed for statically typed concurrent programming using objects, based directly on Milner's pi-calculus. Teaching projects focus on the development of the programming languages area at Indiana University; major goals include a new core course on Type Systems and a course on avant-garde "web languages." ***
