From: jlk@daimi.aau.dk (J|rgen Lindskov Knudsen)
Subject: New OO language for the Macintosh
Reply-To: jlknudsen@daimi.aau.dk (Jorgen Lindskov Knudsen)
Organization: DAIMI: Computer Science Department, Aarhus University, Denmark
Date: Wed, 18 Nov 92 11:36:22 GMT

In responce to the current discussion on available object-oriented
languages  for  the  Macintosh  family, I would like to point your
attention towards the BETA language and the Mjolner BETA System.

BETA  is  a  modern object-oriented language from the Scandinavian
School  of object-orientation with powerful abstraction mechanisms
for identification of objects, classification and composition.  It
has  strong  typing,  whole/part  objects,  reference  attributes,
general block structure, coroutines and concurrency.

BETA is available from Mjolner  Informatics  for  Macintosh with at
least 5 MB RAM, at least a 68020 CPU, and at least MPW 3.1

The  BETA  implementation  has  native  code  generation,  garbage
collection, separate compilation, configuration control, interface
to C and assembly, source-level debugger, and persistent objects.
There  is  a  large  library  of class  patterns  and  application
frameworks.
 - Class patterns for text, file, set, multiset, set with subsets,
   hashtable, list, stack, queue, priority queue, deque, etc.
 - Powerful and easy to use application frameworks on top  of  the
   Macintosh Toolbox.
 - Powerful  metaprogramming system for manipulating  programs  as
   data.
 - Interface to operating system and external languages.
 - Powerful graphical system based on the Stencil & Paint  imaging
   model.
 - Coroutines and Concurrent Processes
   BETA objects may act as coroutines, making it possible to model
   alternating sequential processes  and  quasi-parallel processes.

Inheritance
In  BETA,  inheritance is not only restricted to inheritance  from
superpatterns. It is also possible to inherit from a part  object.
Virtual  patterns in the part object may be redefined to influence
the  enclosing  object. Multiple inheritance is supported  through
inheritance from multiple part objects. This gives a much  cleaner
structure than inheritance from multiple superpatterns.

MacEnv: An object-oriented interface to the Macintosh Toolbox.
MacEnv is a family of libraries abstracting the Macintosh  Toolbox
into an object-oriented framework. Every object in  the  Macintosh
user interface, like windows and menus, has a  corresponding  BETA
pattern definition in MacEnv. The object-oriented abstractions  in
MacEnv is more   general, flexible,  and  easier to use, than e.g.
MacApp of  Apple  Computer, Inc.,  due to the strengths and power-
fulness of the BETA programming language.

Further  information  on the Mjolner BETA System is available from
Mjolner Informatics, please contact mjolner@mjolner.dk

PS: The Mjolner BETA System is also available for UNIX workstations:
    Sun-3, Sun SPARC, HP9000 (300, 400 + 700 series), Apollo 3000 series.
--

   Jorgen Lindskov Knudsen, Mjolner Informatics
   Science Park Aarhus, Gustav Wiedsvej 10, DK-8000 Aarhus C, DENMARK
   E-mail: jlknudsen@mjolner.dk, Phone: +45 86 20 20 00, Fax: +45 86 20 12 22
Newsgroups: comp.sys.mac.oop.misc