HTTP/1.1 200 OK Date: Tue, 24 Nov 2009 03:31:37 GMT Server: Apache/2.2.6 (Fedora) Last-Modified: Wed, 04 Oct 1995 18:27:44 GMT ETag: "73cc8-ac0-6c0c800" Accept-Ranges: bytes Content-Length: 2752 Connection: close Content-Type: text/html; charset=UTF-8

Client extensibility via portable byte-code ("virtual machines")

Reasons PRO

May avoid `language wars' of high-level interpreted extensions if byte-compilers can be written for popular scripting languages.
Better portability than binary extensions.

Reasons CON

Low level of `virtual machine' interface makes meaningful security restrictions difficult to specify.

Applications

Proposed Solutions

Java - an object-oriented, stack-based virtual machine with safe execution and GC features; currently has binding for the Java language (a safe, object-oriented extension to C).
- HotJava browser - Java team (Sun)
- Java Virtual Machine specification
- Java Language overview
- Java Standard Libraries (pre-beta)
Guile - a list-oriented virtual machine with safe execution and GC features, integrated with a lower-level faux-Java byte-code virtual machine. Currently has bindings for Scheme, Tcl, and ctax languages.
- Guile Architecture overview - Thomas Lord (Cygnus)
- TkWWW browser (in progress) - Joe Wang
Low Telescript - stack language apparently supporting suspension and (remote) resumption of execution; see MagicCap Telescript docs for general info (but note MagicCap 1.0 only supports mobile objects, not code...hmm).
Neutral language for a ``safe virtual machine'' - Dave Raggett

Subsidiary Design Requirements

Updated: Sun Sep 3 1995
Up to Client Extensibility.
Home to Interactive Standards Home Page.

HyperNews Responses

1. Portable Byte Code Won't Fly (Guido van Rossum)