On Thu, Nov 17, 2011 at 01:36:38PM +0100, Ralf Hemmecke wrote:
>> Anyway, I see from your response that the approach with sending the
>> Lisp data will not do.
>
> I don't know why you mention LISP all the time. That lisp is the
> underlying system in FriCAS is just a technical detail. If you want to
> communicate with FriCAS, you should do it in SPAD, or rather in the
> interpreter language of FriCAS. Just send to FriCAS the same text that
> you would put into a *.input file in order to compute what you want.
> Then parse the output (basically a big string) by Haskell means back
> into something that docon understands.
I thought that the cost of parsing by FriCAS from *.input is much
greater than the cost of the proper evaluation. This is parsing a
Spad program and data from a string, it involves analysing arities,
setting parentheses, and so on, a generic syntax is complex to parse.
The matter is that in a CAS, the output string needs to look nice, but
it is usually difficult to parse from, takes quite a cost.
This is why I thought of the interface at such a level where most of
parsing is ready, an I thought that it was Lisp.
I have already forgotten of Lisp, all right.
Now I see, how to use only a string interfcace, *.input and Spad.
Certain operations must prepare a string which represents a data which
is "almost parsed". And these operations are programmed in Haskell and
in Spad.
>> [..]
>> class AxiomParse a where toAxiom :: a -> String
>> fromAxiom :: a -> String -> a
>> [..]
>>
>> Similarly, Category DoConParse(a) {fromDoCon : String -> a,
>> toDoCon : a -> String}
>> is added to the Axiom library
>
> Well, of course, you can put the parse-part on the SPAD or on the
> HASKELL site, whatever is better for you, but if Docon directly produces
> the command line syntax of FriCAS, then FriCAS can basically just take
> your string and execute it, because there is already a builtin parser
> for the interpreter language.
Again, I expect that this builtin parser of FriCAS will parse the data
like "f = (x^2 + 4*x*y + 5*y**3)" much longer (probably) that it takes
the proper evaluation of factorIntPoly_axiom(f).
Instead I intend to write in Spad
let str = inputFromSocket;
f = fromDoCon str;
res = factorIntPoly_axiom(f);
resStr = toDoCon res;
in outPutToSocket resStr
(change the syntax to FriCAS).
And this is put in *.input for FriCAS.
Here str is easy to parse by fromDoCon, because it is prepared so,
and fromDoCon is programmed (in Spad) specially for this format of
str.
Regards,
------
Sergei
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