From: baird@maillol.inria.fr (Anselm.BairdSmith)
Newsgroups: comp.lang.scheme
Subject: OScheme, new release
Date: 20 Mar 1995 18:38:48 MET
Organization: I.N.R.I.A Rocquencourt
Distribution: world
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OScheme, version 2.1 is now available.  Oscheme stands for Objective
Scheme. It is an embeddable scheme interpreter conforming (mostly) to
R4RS. Lots of non-R4RS extensions are provided:

- regular expressions,
- system utilitites,
- process and socket modules (for UNIX only)
- autoload (both for scheme and object modules)
- autodoc package, to generate both on-line and HTML documentations
  from C and scheme sources.

It also includes a prototype-based object model:

	The new syntactic form:

    [object {selector: args}* {selector}?]

    extends scheme exactly like objective-C extends C syntax, "a la
smalltalk". This object model is prototype-based. Foreign language
structures can be turned into this kind of objets, which allows
end-programmer to extend them with new slots, and new methods, both in
C and in Scheme.

OScheme is delivered as a standard library, which can be extended
through a C API, to:

	- declare new pritimive functions,
	- add primitive types
	- add foreign structure, by making them scheme prototype objects.

Finally, it uses a conservative GC.

Beyond this, it is a (stack-based) byte-coded interpretor, with the
byte compiler written in C. It compares favorably (in speed, at least)
with current embeddable interpretors (benches written on top of the
Meroon object system - by Christian Queinnec - have run two times
faster with OScheme than with SCM).

Available extensions provide a scheme interface to the X Motif
toolkit, and the CERN WWW library. 

Under work is a "secure" version of OScheme that allows to run Scheme
scripts within a reduced environment, "a la" safe-tcl. The current
release already provides some support for multiple global environments
and execution contexts (see the URL below for more informations).

The full package can be retreived from:

    ftp://indri.inria.fr/pub/OScheme/oscheme.tar.gz
or,
    http://www.inria.fr/koala/abaird/oscheme/oscheme.html

Anselm.




-- 
-----
Anselm BAIRD-SMITH (Anselm.BairdSmith@inria.fr), Koala Project, BULL/INRIA.
WWW: "http://www.inria.fr/koala/abaird.html"