String Handling in ALGOL

DASH is designed to allow a user to handle strings and perform efficient arithmetic in the same language. There are a number of languages designed to handle strings (Farber, Griswold and Polonsky, 1964 and 1966; Guzman and Mclntyre 1966), but their arithmetic facilities are slight. On the other hand, on many computers the only "general purpose" languages at present implemented (e.g. ALGOL 60, FORTRAN) are almost purely arithmetic. This hampers both users and those whose job is computer science education. The procedures to be described aim to provide string processing of the SNOBOL type (Farber et al, 1966) to the extent that is reasonably possible within ALGOL. The description is informal, and some details are omitted for brevity. The reader will benefit from a knowledge of SNOBOL, though it is hoped an understanding can be gained without this knowledge. The superimposition of procedures of this type on ALGOL will be rendered easier and more natural with a facility such as the proposed record handling of Wirth and Hoare (1966).