Path: utzoo!utgpu!watmath!iuvax!purdue!decwrl!bartlett
From: bartlett@decwrl.dec.com (Joel Bartlett)
Newsgroups: comp.lang.lisp
Subject: Re: Looking for an embedded lisp.
Message-ID: <1362@bacchus.dec.com>
Date: 24 Apr 89 21:57:08 GMT
References: <12458@pasteur.Berkeley.EDU>
Organization: DEC Western Research Lab
Lines: 62

Another embeddable LISP you might consider is Scheme->C done at DEC WRL
which is available NOW:

The compiler compiles Revised**3 Scheme to C that is then compiled by
the native C compiler for the target machine.  This design results in
a portable system that allows either stand-alone Scheme programs or
programs written in both compiled and interpreted Scheme and other
languages.

Licensing mechanics.

License and software distribution is via paper mail so I will need
your postal address.  There is a distribution fee of $100
(U.S.) for the software.  Software is distributed on a tar tape in
source form.  Like any other research software, it's on an "as is"
basis.  If your organization is unwilling to sign the license and you
still want the software, we'll have to discuss it.

Computer systems licensed.

Currently the system runs on top of ULTRIX.  It has also been run on
4.2 BSD UNIX.  A VMS version has not been made, but it can probably
run under Eunice.

While the software was designed to be portable and has been ported to
three different processors, the terms of the license currently restrict the
software to Digital VAX and DECstation 3100 computers.

Is it really Scheme?

The system supports the essentials (including cwcc) of Revised**3 and many of
the optionals.  Extensions include "expansion passing style" macros, a
foreign function call capability, and full support of X11's Xlib.  Numbers
are represented internally as 29-bit integers, or 64-bit floating point
values.

The system is oriented towards block compilation to generate code
which can run in standalone programs which may include code from
other languages.  While debugging is typically done using the
interpreter, it will never be considered a "Scheme environment".

The one "wart" in the system is that the compiler cannot compile all
tail calls correctly.  This follows from some of the design tradeoffs
made when mapping Scheme to C (see tech report). 

The compiler is written in Scheme.  Most of the runtime system
(including an interpreter) is written in Scheme.  The compacting garbage
collector and a few other things are written in C.  There is a small
(< 100) amount of assembly code.

Tech report available

A technical report provides details about the design.  It includes
some sample code, benchmark data etc.  To see the abstract, get a
hard copy, or a Postscript file, send a message with "help" in the subject
line to:  wrl-techreports@decwrl.dec.com.

  
If you have specific questions or are interested in license information,
contact me directly.

	Joel Bartlett   bartlett@decwrl.dec.com