wyant@apollo.uucp (Geoffrey Wyant) (08/22/86)
I just recieved my copy of Smalltalk/V from Digitalk. All in all
I think they did an amazing job given the limitations of the PC.
The system comes on 3 diskettes, one containing the interpreter &
virtual image, one containing the sources, and one containing a tutorial
and useful programs (freehand drawing package, etc.). The interpreter
diskette can be removed after the interpreter is started up. The
sources diskette should remain in drive B.
The biggest question one might ask is how well does it perform ?
Surprisingly well, actually. The entire user interface
(editor, et. al) is written in Smalltalk, and you wouldn't think
that you were using an interpreted user interface with its
responsiveness. Editting is fast, and menus pop up with reasonable
speed. Evaluation of (medium-sized) expressions seems to happen
quickly enough. Things you might expect to be slow are slow.
Creating a new window takes several seconds (~5-10 secs.)
The class library is exceedingly large, with about 102 classes, and
something like 2000 methods. Smalltalk source code for all classes
and methods is supplied (in compressed form) on the source disk.
A nice browser is included for looking at the class sources and
adding new classes and methods. I think most all the classes
described in the blue book are implemented. A few of the graphics
subclasses (Path,...) have been omitted and the Process class is
different. Also I don't think Digitalk based Smalltalk/V on the Xerox
ST80 virtual image, and so there are some differences in the user
interface. It seems to have something similiar to, but slightly
different from the standard model-view-controller paradigm.
The tutorial diskette besides having a set of tutorial files, has
some very usefull utilities. The freehand drawing package is on
there, as well as a file browser. They also have a prolog compiler,
but I haven't had time to play with it yet. Another usefull item
is the disk browser for moving around directories and looking at
individual files.
In terms of hardware, it seems to work reasonably well on my
2 floppy system, but needs a hard disk if you intend to use their
object-swapping feature. A minimum of 512K memory is needed. It
can be used with a CGA adapter, but only if you like self-abuse.
The manual is very well written and comes in two sections. The first
section is a tutorial and the second is the class encyclopedia. The
tutorial section includes about 12 pages on writing a user interface.
the class encyclopedia is 200 pages long and describes each class, and
the methods implemented by that class. Included are appendices on
interfacing with assembly language and tips on configuring the system.
My overall impression is highly favorable. For $100, I think this is
quite an impressive system considering that the alternative is
SoftSmarts system for the AT which costs $1000, requires a hard disk
and an EGA. I have no affiliation with Digitalk, I'm just a very
satisified customer.
--
Geoff Wyant UUCP: ...{yale,uw-beaver,decvax!wanginst}!apollo!wyant