According to Frank Heckenbach:

How do you know about PXSC, anyway?

Everything I know about PXSC is from one book, "Pascal-SC", in German only, I once have found at our library. I was impressed by the possibilities of exact (!) numerical calculations, and operator overloading.

I did a Yahoo search on "PXSC", and it showed quite a few interesting things about PXSC (besides a few other things abbreviated by "PXSC" and several links to gpc pages :-), e.g. PXSC "home pages":

http://ma70.rz.uni-karlsruhe.de/~ae25/iam/html/language/xsc-sprachen.html http://wwwma.rz.uni-karlsruhe.de/~ae08/iam/html/language/pxsc.html

I also learned about even more Pascal extensions, like XL Pascal and Pascal++ (see http://www.informatik.uni-halle.de/lehre/pascal/sprache/pas0.html).

When I have the time :-( I "must" have a look at those pages. Maybe we can find more interesting ideas for GPC there ...

On a page about BP, I found this remarkable statement: "Borland is the leader in Object-Oriented Programming, winning more awards for technical innovation and customer support than anyone else. That means that when you use Turbo Pascal, you're guaranteed to have the best development environment available, backed by the best support available. It's Borland's commitment to you. [...] Copyright ) 1995 Borland International, Inc." Things must have changed very much within 2 years... :-(

That's just the problem: They didn't change (read: improve) anything since 2 years and more.

...

Think of a schema as a type declaration with parameters which can occur anywhere in the declared type: as array or subrange boundaries, or as a variant record selector.

Anywhere??? (roots:array[1..1+ord(sqr(p)/4-q<>0)] of complex;-)

Schema discriminants must be ordinal types, but the following compiles:

Type roots ( p, q: Integer ) = array [ 1..1 + ord ( sqr ( p ) / 4 - q <> 0 ) ] of Complex;

However it is useless since

Var x: roots ( 4, 4 );

crashes GPC. Expressions in schemata don't seem to work at all currently.

[long numbers]

Not really the whole library; multiplying a long number by 10 (or any base) would be relatively easy to do manually. But you're right, it won't probably be needed too often, so this little inefficiency of the conversion at runtime seems tenable... :-) ... except, maybe, if PXSC demands it ...?

The compiler would have to deal with expressions formed by such numbers. Better leave this for a library.

Peter

Dipl.-Phys. Peter Gerwinski, Essen, Germany, free physicist and programmer peter.gerwinski@uni-essen.de - http://home.pages.de/~peter.gerwinski/ [970201] maintainer GNU Pascal [970624] - http://home.pages.de/~gnu-pascal/ [970125]