Re: [Axiom-developer] Aldor and Lisp

[Martin Rubey]

Dear all,

concerning the freeing of Aldor, Ralf told me a week ago or so that there is
some hope. It seems that Stephen is looking at the issue, but "it's not settled
yet".

 > > An alternative that does exist (maybe) is to make incremental improvements
 > > to Axiom's built-in SPAD compiler that would make it more compatible with
 > > Aldor. In effect this would amount to "back-porting" some of the
 > > improvements that where made to the SPAD language when Aldor was
 > > originally implemented. The result will be a compiler that works within
 > > Axiom to write better Axiom library code. But it would not have the option
 > > of running as a stand-alone compiler the way Aldor can now.
 > 
 > This is the option that appears best to me.  It is certainly simpler, and I
 > don't think we have much use for a standalone aldor compiler in the axiom
 > community.

As you probably know by now, this is my favorite option, too. I would like to
point out, that we will not be able to use "full" Aldor for Axiom, even if it's
free, since the Axiom interpreter doesn't understand dependend
types. Generators and exceptions don't seem to be so important to me. In fact,
concerning generators, I don't see the advantage over Stream yet.

And I think that Spad should be improved by using boot or common lisp. Not yet
another language to learn! Spad/Aldor itself would be acceptable to me, but as
I detailed before, I think it will be easier to attract Lisp knowledge than
anything else. (Thanks Camm, by the way, for supportin my post!)

 > > I still think however that even improving SPAD will not be easy.  It will
 > > require rather deep knowledge of the largely undocumented legacy code that
 > > currently implements SPAD in Axiom.

We will need this knowledge anyway to understand the interpreter, I guess.

 > > It is notable I think, that the original Axiom developers chose to
 > > re-implement SPAD as Aldor (written in C) rather than continue to make
 > > improvements to SPAD.

I'm absolutely certain that the reason for this was rather a political than a
technical one.

 > Is SPAD irreparably deficient in some way?

definitely not. Note however that there is *no* Aldor -> Spad translator. There
is however a Spad -> Aldor translator, which mainly transforms pile syntax
(i.e., indentation sensitive style) to the "nopile" syntax (i.e., blocks
delimited by braces.)

I can deal with both syntaxes and Aldor does so, too.

I do think that the Spad compiler could need improving, but my goal is rather
to have a good Algebra hierarchy and sufficiently many developers. A dozen is
just not enough. And, moreover, we need to attract more genuine mathematicians,
i.e., researchers. If this doesn't change within a year or so, Axiom is
probably doomed to die. In this vein, getting into contact with Singular is the
one of the best things that could happen to us. A second community, that is
*huge* and were several people are interested in contact is R. By coincidence,
the sit in Vienna, and I'm at the institute of statistics currently. So I
guess, this is my job. I'll post a message, I think.

Martin