On Mon, 5 Jun 2006, Martin Rubey wrote: | Gabriel Dos Reis <[EMAIL PROTECTED]> writes: | | > On Mon, 5 Jun 2006, Martin Rubey wrote: | > | > | Gabriel Dos Reis <[EMAIL PROTECTED]> 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:
I think it is a good idea, given the current constraints. | 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!) Yes, type inference is of the area that I was thinking of. Aldor's requirement of System F-style explicit polymorphism is way too heavy. We should have syntaxes so that in the simple cases, the system infers the type -- full type inference in unreasonable and foolish to seek for. | The benefit would be that we would have Aldors power available at the | interpreter level. Agree. | 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. Yes, I agree. However imperfect it is, it has the virtue that its source code is available so that people can improve it. -- Gaby _______________________________________________ Axiom-developer mailing list Axiom-developer@nongnu.org http://lists.nongnu.org/mailman/listinfo/axiom-developer