1.1 Opening Remarks

This document describes PSL (Portable Standard Lisp 1), a portable, ”small” and fast LISP developed originally at the University of Utah and the Hewlett-Packard Company. The present version of PSL is supported by the Konrad–Zuse-Zentrum Berlin. PSL is upward-compatible with Standard Lisp 2. In most cases, Standard Lisp did not commit itself to specific implementation details (since it was to be compatible with a portion of ”most” LISPs). PSL is more specific and provides many more functions than described in that report.

The goals of PSL include:

• Providing implementation tools for LISP that can be used to implement a variety of LISP-like systems, including mini-Lisps embedded in other language systems.
• Effectively supporting the algebra system on a number of machines.
• Studying the utility of a LISP-based systems language for other applications (such as CAGD or VLSI design) in which Lisp code provides efficiency comparable to that of C or BCPL, yet enjoys the interactive program development and debugging environment of LISP.