Re: [Axiom-developer] B natural

[Martin Rubey]

Gabriel Dos Reis <address@hidden> writes:

> On Mon, 5 Jun 2006, Martin Rubey wrote:
> 
> | Gabriel Dos Reis <address@hidden> writes:
> |
> | > Also, I have been looking for the a formal grammar description of SPAD.
> | > Where can I find it?  The AXIOM book seems silent about it....
> |
> | Forget about SPAD, go for Aldor.

> The source code of the Aldor compiler is not available; SPAD's is.  I heard
> there are talks tomove on that front, but how long we have to wait.  I cannot
> tell my students to wait till next year or so.

> Yes, of course I can initiate a mini project where where they will build an
> Aldor-like translator, but I rather have them start with a base code and add
> transformations or type system convenient features.

A very useful project -- of course, I don't know whether it fits your needs --
would be the following:

The Aldor interpreter is very weak, it segfaults quite often, it has no way to
figure out "likely" types and so on.

So maybe, you and your students could figure out how to make the axiom
interpreter do the type guessing etc., but then call the aldor compiler,
instead of using SPAD. (If this description is too vague, please complain!)

The benefit would be that we would have Aldors power available at the
interpreter level.

I guess you know already that SPAD has various shortcomings, the two major ones
probably being: 

* Types are not first class objects (i.e., no Lists of Types), 

* SPAD doesn't have truly dependent types.

Martin