From: hoelzle@Xenon.Stanford.EDU (Urs Hoelzle) Subject: Announcing Self 3.0 Date: 28 Dec 93 22:19:34 GMT
ANNOUNCING Self 3.0 The Self Group at Sun Microsystems Laboratories, Inc., and Stanford University is pleased to announce Release 3.0 of the experimental object-oriented programming language Self. This release provides simple installation, and starts up with an interactive, animated tutorial. Designed for expressive power and malleability, Self combines a pure, prototype-based object model with uniform access to state and behavior. Unlike other languages, Self allows objects to inherit state and to change their patterns of inheritance dynamically. Self's customizing compiler can generate very efficient code compared to other dynamically-typed object-oriented languages. The latest release is more mature than the earlier releases: more Self code has been written, debugging is easier, multiprocessing is more robust, and more has been added to the experimental graphical user interface which can now be used to develop code. There is now a mechanism (still under development) for saving objects in modules, and a source-level profiler. The Self system is the result of an ongoing research project and therefore is an experimental system. We believe, however, that the system is stable enough to be used by a larger community, giving people outside of the project a chance to explore Self. 2 This Release This release is available free of charge and can be obtained via anonymous ftp from Self.stanford.edu. Also available for ftp are a number of published papers about Self. There is a mail group for those interested in random ramblings about Self, Self-interest@Self.stanford.edu. Send mail to firstname.lastname@example.org to be added to it (please do not send such requests to the mailing list itself!). 2.1 Implementation Status Self currently runs on SPARC-based Sun workstations running SunOS 4.1.x or Solaris 2.3. The Sun-3 implementation is no longer provided. 2.2 Major Changes Below is a list of changes and enhancements that have been made since the last release (2.0.1). Only the major changes are included. o The graphical browser has been extended to include editing capabilities. All programming tasks may now be performed through the graphical user interface (the "ui"). Type-ins allow for expression evaluation, menus support slot editing, and methods can be entered and edited. If you are familiar with a previous version of the Self system, Section 14.1 of the manual entitled "How to Use Self 3.0" contains a quick introduction to the graphical user interface. The impatient might want to read that first. o A mechanism - the transporter - has been added to allow arbitrary object graphs to be saved into files as Self source. The system has been completely modularized to use the transporter; every item of source now resides in a transporter-generated module. Transport-generated files have the suffix .sm to distinguish them from "handwritten" files (.Self), though this may change as we move away from handwritten source. The transporter is usable but rough, we are still working on it.
o Every slot or object may now have an annotation describing the purpose of the slot. In the current system, annotations are strings used to categorize slots. We no longer categorize slots using explicit category parent objects. Extra syntax is provided to annotate objects and slots. o A new profiler has been added, which can properly account for the time spent in different processes and the run-time system, and which presents a source-level profile including type information (i.e., methods inherited by different objects are not amalgamated in the profile, nor are calls to the same method from different sites). It also presents a consistent source-level view, abstracting from the various compiler optimizations (such as inlining) which may confuse the programmer. o Privacy is not enforced, although the privacy syntax is still accepted. The previous scheme was at once too restrictive (in that there was no notion of "friend" objects) and too lax (too many object had access to a private slot). We hope to include a better scheme in the next release. o The "new" compiler has been supplanted by the SIC ("simple inlining compiler"), and the standard configuration of the system is to compile first with a fast non-optimizing compiler and to recompile later with the SIC. Pauses due to compilation or recompilation are much smaller, and applications usually run faster. o Characters are now single-byte strings. There is no separate character traits. o Prioritized inheritance has been removed; the programmer must now manually resolve conflicts. We found the priority mechanism of limited use, and had the potential for obscure errors. 2.4 Bug Reports Bug reports can be sent to email@example.com. Please include an exact description of the problem and a short Self program reproducing the bug. 2.5 Documentation This release comes with two manuals: How to Use Self 3.0 (SelfUserMan.ps) The Self Programmer's Reference Manual (progRef.ps)
-- The Self Group
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