RE: [Axiom-developer] Re: libaxiom.a

[Bill Page]

On March 29, 2006 5:09 PM Ralf Hemmecke wrote:
> 
> Maybe some people are very accustomed to SExpressions, I am
> not. I am perfectly happy with Lists whose elements have a
> particular type, for example, "List(Boolean)". Sexpressions
> are already a bit more complicated. And I cannot belief that
> they are the most natural thing that a mathematician can
> think of.
>

I am not sure how to define "natural" but the concept of an
S-expression was certainly invented by a mathematician. If you
haven't already read, it I think John McCarthy's paper original
1960 paper:

http://www-formal.stanford.edu/jmc/recursive.html

"RECURSIVE FUNCTIONS OF SYMBOLIC EXPRESSIONS AND THEIR
COMPUTATION BY MACHINE"

See also

http://www-formal.stanford.edu/jmc/index.html
http://www.paulgraham.com/rootsoflisp.html
 
>  > Aldor is designed to compile to Lisp as one option.
> > It is natural to continue to use this in Axiom.
> 
> I am not against LISP. If code can be re-used then it's fine.
> But there was already someone on the list who said that it 
> would not be so easy to build a (symbolic-algebra) object
> library that could be linked to Fortran or C (or any other
> language) programs.

Why?

> 
> Anyway, that Lisp discussion is quite useful for me. In Axiom
> I am sometimes missing the "Rep" of a domain.
> 
>    src/algebra/boolean.spad.pamphlet
> 
> Now I belief, that in such a case the representation is an 
> SExpression.  Wrong?
> 

Exactly right! The representation is inherited from Lisp.
I think that it should be acceptible to write:

  Rep == Lisp

just like we can write $Lisp In other words from the point
of view of SPAD and Aldor Lisp should appear just like a
pre-defined domain.

Regards,
Bill Page.