(PSI) A portable scheme interpreter by Ozan Yigit oz@ursa.sis.yorku.ca , David Keldsen and Pontus Hedman that includes a simple DAG compiler and a virtual machine . It can be used as an integrated extension interpreter in other systems and allows easy addition of new primitives. There are some unique debugging and tracing facilities. Acceptable performance results from a fairly straight-forward implementation. Continuation s are fully and portably supported and perform well. PSI is based on the simple compilers and virtual machine in Kent Dbyvig's thesis.
The pre-release version conforms to R4RS with a number of useful extensions.
(1993-02-19)