Re: [Gm2] Dynamic arrays?!?

[Gaius Mulley]

Martin Kalbfuß <address@hidden> writes:

> I'm a bit confused. You're talking about multidimensional dynamic arrays
> in the news. I don't get even a simple dynamic array working.
>

Hi Martin,

multidimensional dynamic array _parameters_ as per ISO.  PIM[234]
defined the behaviour of uni dimensional dynamic array parameters.
So you can now:

PROCEDURE foo (a: ARRAY OF CHAR) ;
VAR
   h: CARDINAL ;
BEGIN
   h := HIGH(a)
END foo ;


as well as:

PROCEDURE bar (a: ARRAY OF ARRAY OF CHAR) ;
VAR
   h: CARDINAL ;
BEGIN
   h := HIGH(a[0])
END bar ;

> What's the way to go? ALLOCATE and pointer arithmetic? Or is there
> anything I missed? The resources on the net wasn't very helpfull at all.

yes this is probably the way to go if you want the equivalent of the GNU C
constructs:

   char a[n];

or in C (without GNU extensions)

   char *a = (char *)alloca(n);

then the equivalent in Modula-2 might be:

VAR
   a: POINTER TO CHAR ;
BEGIN
   ALLOCATE(a, n) ;
   ...

   DEALLOCATE(a, n)
END

and you would have to manage the array arithmetic yourself though..

regards,
Gaius