ORG, GEN Re:arf2 [djg12]

Michael David WINIKOFF
Mon, 29 Mar 93 10:22:09 EST

> The design phases are:
>         1) requirements
>         2) general design
>         3) detailed design
>         4) coding
>         5) testing
> Now I will admit, phase 1 is done.  Our requirement is for a "Multi-
> tasking Object oriented Operating SystEm" (thus MOOSE).  But we
> haven't yet managed to finish the general design, so we should at most  
> be doing some preliminary work on the detailed design and coding
> experiments that are considered, in the long term, junk; but WE AREN'T
> If I seem a bit intense about this, it is because I have seen what
> happens to a large project if there is appropriate design before
> coding begins.  In this case, I would expect that if we start coding
> now, we will in not less than two years have something that can be
> compared unfavorably with Windows 3.0, and that isn't good.

The only large (relatively) scale project I was involved with spent ages on 
the design -- the coding want very smoothly (especially considering it involved
shared memory, semaphores, spin locks etc.)

I would like however to point out exploratory programming -- this is where you
can't decide exactloy what you want so you build prototypes of the sywtem which
wil later be rewritten.

> ======
> I would say that what we need to do now is determine:
>    1) What the kernel will do and what the rest will do.
>    2) How messages will be sent to objects.  (This has been called
>       ROI.  PLEASE don't think that means it is seperate from the
>       kernel.)
> This more or less defines the kernel.
> Then we get then detailed design:
>    1) What are the classes?  Most of the class hierarchy?
>    2) What are the common methods?
>    and about 10 times more stuff, most of which probably won't be
>       obvious until we get there.... (or even into coding....)
> AFTER that we code.

Yes. Coding the system now is WRONG.
Knocking up bits of code to test ideas is good.

> -- 
> David Garfield/2250 Clarendon Blvd/Arlington, VA 22201   (703)522-9416
> Email: or

Michael Winikoff
Computer science honours. University of Melbourne, Australia.