The initial implementation of PAL, in Lisp, was written by Peter Landin and James H. Morris, Jr. and ran on the Compatible Time-Sharing System (CTSS). It was later redesigned by Martin Richards, Thomas J. Barkalow, Arthur Evans, Jr., Robert M. Graham, James Morris, and John Wozencraft. It was implemented by Richards and Barkalow in BCPL as an intermediate-code interpreter and ran on the IBM System/360; this was called PAL/360.[4]
RPAL
The Right-reference Pedagogic Algorithmic Language (RPAL), is a functional programming subset of PAL with an implementation on SourceForge.[5] It is used at the University of Florida to teach the construction of programming languages and functional programming. Programs are strictly functional, with no sequence or assignment operations.
^John M. Wozencraft and Arthur Evans, Jr. Notes on Programming Linguistics. Unpublished report, Department of Electrical Engineering, MIT. February, 1971.
^Arthur Evans, Jr., "PAL—a language designed for teaching programming linguistics" Proceedings of the 1968 23rd ACM National Conference (August 27–29, 1968), p. 395-403 ACM abstract