Shared functions and variables as an aid to applications design

Abstract

Analogic APL incorporates true sharing of named objects into APL for the first time. Both functions and variables may be shared. True shared variables are variables which are visible and accessible to multiple tasks without the aid of any intervening processor. They fill roles traditionally taken by shared file systems and (@@@@)SVO-style shared variables. Their straightforward design allows an APL programmer to develop whatever sharing protocol is most appropriate to the application. One could, for example, build a complete shared file system or (@@@@)SVO-style shared variable processor written in APL. All of the features of Analogic APL discussed in this paper have been fully specified. The system is now being implemented. A substantial subset of these features will be demonstrable in Helsinki in June, 1984.