curses suggestions wanted_(re)

Wed, 6 Aug 1997 19:21:55 +0200 (MET DST)

According to Ken Linder:
> 
> While working on a curses (ncurses) interface I have come upon a situation
> whereby I need some directions from potential GPC ncurses users.  Certain
> ncurses functions require a PCHAR pointing to a string for the function to
> use.  Would you, the potential users, rather pass a string schema instead?

Yes, but this is no real problem (see below).

> Personaly I would like an ncurses lib where I only pass strings when I can.
> 
> Any ideas or suggestions?
> 
> I could also allow either type of call...
> 
> C style:
>       addstr(PChar);
> 
> GPC style
>       gaddstr(String);

In such situations, where the procedure/function does not change the
parameter, you can declare it with a `PChar' parameter.  GPC knows what
to do if the user passes a String schema and implicitly passes the address
of the string data instead of the address of the schema.

OTOH if the String is in fact a `Var' parameter (I don't know if such
functions exist in [n]curses), you must decide whether this shall be a
`PChar' or a String schema.  In such cases I would prefer to have the
`String' variant as the default and the `PChar' variant as an extensions,
i.e.

  C style:
      Procedure cfoo ( Var S: pChar );

  GPC style:
      Procedure foo ( Var S: String );

(* NB:  You needn't specify the length of the string in `Var' parameters,
but you must do so for the return value of a function. *)

Greetings,

    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 [970714] - http://home.pages.de/~gnu-pascal/ [970125]

Peter Gerwinski (peter@agnes.dida.physik.uni-essen.de)