SPITBOL compiler

SPITBOL (Speedy Implementation of SNOBOL) is a compiled implementation of the SNOBOL4 language. Originally targeted for the IBM System/360 and System/370 family of computers, it has now been ported to most major microprocessors including the SPARC. It was created by Robert Dewar and Ken Belcher who were then at the Illinois Institute of Technology.

Prior to the development of SPITBOL, SNOBOL4 was thought to be slow, memory-intensive, and impossible to compile due to its dynamic nature. While delayed binding prevents everything from being determined at compile time, SPITBOL is very clever about making decisions as early as possible. SNOBOL4 programs run under SPITBOL are amazingly fast. Notable is the SPITBOL garbage collector which runs extremely well under the most constrained conditions.

One contribution of SPITBOL to computer science was to demonstrate the clear distinction between a language and its implementation. Rather than stating that a language itself is slow, it is more accurate to say that the ability to write a fast and elegant implementation is a rare gift. The same issue is current with Java, which is often erroneously called an interpreted language – common implementations may be interpreters, but the language is just the language.

Recent versions of the SPITBOL compiler are available. Since 2001 the source code for the original SPITBOL 360 compiler has been made available under the GNU General Public License. [ [http://www.snobol4.com/spitbol360/ Spitbol source and Documentation] ]