LISPF4 is an InterLisp interpreter written by Mats Nordstrom from Uppsala, Sweden in the early 80's. It was written in FORTRAN, and found by me, over the course of a few years of use, to be quite stable. I subsequently used the F2C program to convert it to C. I then gave it the ability to have command-line determination of the memory size. I have much less experience with the C port in terms of reliability.
The original FORTRAN code required a small assembler piece to provide byte indexing into integers. This small piece caused no end of trouble when porting to a new compiler. Since C can do this without assembler, this problem has hopefully been eliminated.
The system supports much of the InterLisp standard, and a few bits of the standard were added by me. There is no GUI. Sometime in the late 90's Mats was kind enough to give me a copy of the latest version he had (8/22/83). He also gave me permission to release it so long as I retained his credits. Among other things, this distribution includes the entire, untouched, original source code and documentation.
The current status of the C conversion eliminates the need for a FORTRAN compiler or F2C. It is all C code now. I've had it working on Windows, Mac, and Linux.
Interlisp is a dynamically scoped lisp system. It supports LAMBDA (evaluates function arguments), NLAMBDA (doesn't evaluate its arguments), and variable number of arguments. Macros are supported as well.
The system comes with a pretty complete user manual and implementors manual. I also include the documentation this system is based on.
Pre-built systems for Linux, Mac, and Windows are also included.
See the Documentation/README.txt file for more complete documentation.
The master copy of this system is located at: https://github.com/blakemcbride/LISPF4
Enjoy.
Blake McBride