Re: Miscellany (Memory and String handling)

[td@almeria.inria.fr (Thierry Despeyroux)]

In article <56574@sophia.inria.fr>, kuehne@isa.informatik.th-darmstadt.de (Thomas Kuehne) writes:

|> 1. Memory
|> 
|>   We have heavy, heavy Memory problems. Yet small specifications are 
|>   hardly executable.
|>   We suffer from "Mu-Prolog out of memory".
|>   We use a centaur+ with GSTKLEN=8000000 on a SPARCstation10 with 32MB.

I'm afraid that there is no good solution with MU-Prolog. (MU-Prolog
is known to be bad for memory management). You can use "once" in Typol when
you know that some parts of your specification is deterministic. I hope that
the use of Eclipse (a compiled prolog with garbage collection and dynamic stacks)
will cure this problem in the futur.


|> 2. String handling
|> 
|>   We use SDF for Syntax and TYPOL for Semantics.
|>   We see no way how to convert all Uppercase Letters into Lowercase.
|>   SDF offers no means here and with TYPOL and PROLOG there is no
|>   access to "atomic" strings.

import lowercase(string,string) from prolog;

By chance, I added this predicate to MU-Prolog because it is used by the Typol compiler.
You can also use Lisp to manipulate strings (as someone did it for reals). May be it
is not very efficient. It is also possible to link dynamically c procedures to a
prolog predicate. Eclipse will also provide this feature. A good solution for this sort
of problem. 

However, if you need to convert all uppercase letters into lowercase and this is not
related to the semantics, you can do it very easily in Lisp. It is just a tree walk
that modify the value of atomic nodes.

Thierry


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|     Thierry Despeyroux      | email: Thierry.Despeyroux@sophia.inria.fr   |
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