An implementation of 'blocks' in SPITBOL

Abstract

A relatively new datatype, called a block, was designed and implemented by James F. Gimpel in the SNOBOL4 programming language[1,2]. SNOBOL4[3] being an interpreter, requires significantly more execution time and memory than a compiler. To overcome this deficiency, Robert B. K. Dewar and Kenneth E. Belcher, at the Illinois Institute of Technology, designed a speedy implementation of SNOBOL4 known as SPITBOL[4]. SPITBOL is a compiler, it requires less time and memory than SNOBOL4. At the time SPITBOL was written, the block datatype was not included. This paper describes an external routine which was developed to add the block datatype to SPITBOL. The availability of blocks in SPITBOL opens many new paths for data structures in the field of non-numeric applications. Three dimensional data structures can be used in many areas of computer science. For example, l) Computer Graphics, displaying three dimensional geographic locations on a two dimensional surface; 2) Artificial Intelligence, scene analysis and mechanical theorem proving; and 3) Business Applications, displaying reports and statements (overprinting to highlight important items).