Re: [Axiom-developer] BAD tim

[Scott Morrison]

Hello everybody,

This is my first posting to this list.  I worked at IBM Research
off and on for 9 years.  I'm the primary author/designer of the
interpreter and HyperDoc, and I wrote the first code generator and
optimizer for Aldor (then called A#).

I found Tim's posting very interesting, and I just had to comment.  (Hi Tim!)

>>POINT 3: Boot is a dead language. 
>>
>>   There are approximately 10 people still living who have coded in
>>   boot and every one of them is doing something else with their
>>   life.

Being one of those 10 people, I have to agree with Tim and his opinion
of the Boot language.  Dick Jenks told me that boot was to be the
first step in implementing the entire system in the Spad
language.  Once the syntax looked like Spad, the next step would
be to convert it to real Spad.  Of course that never happened, so
the main purpose behind Boot is gone.

In my opinion Boot can be a convenient language to code in, but it has
two main problems.  The use of indentation for grouping is just a
bad idea.  It works well for one-page programs, but with anything
with reasonable complexity, it falls down.  Just adding braces to
Boot for grouping would go a long way to making it more usable. 
The other problem is the lack of a way to structure data.  I fully
agree with Tim on the  problems with that language.

>>I'm the only person likely to be hacking
>>   the interpreter for the near future, mostly because it is so big,
>>   ugly, unstructured, and undocumented.
Ouch.  The truth hurts.  Believe me, when I started writing
the interpreter some 21 years ago, I never imagined it would have such
a long life.  This was my first major programming project out of
college.  After 20 years of experience, I would do a lot of things
differently today.  These days I'm too busy with my current job
(graphics programming at Audtodesk) to be able to devote any time to
the Axiom project.

>>There is no reason (other than historical) why there are
>>   a dozen entry points into the interpreter that set wierd, undocumented,
>>   stateful flags. All that cruft must go away.

Good luck Tim.  As the author of much of this cruft, I think you
have your work cut out for you.  Maintaining functionality while
refactoring the code will be a major challenge.  Your two year
estimate seems about right if you are planning on working on this full
time.  If not, I think two years is optimistic.

I think the transition from Boot to Lisp could be done in an
incremental way, converting modules gradually, thus maintaining the
integrity of the system during the conversion.  However, I agree
that converting to Lisp ultimately is the right thing to do.

I'm on the axiom-developer list now, so I can answer the occasional
question, but I won't have much time for this project, unfortunately.

-- Scott Morrison (SCM)