Re: Prefix to 'ACCESS must either statically match... But why?

["James S. Rogers" <jimmaureenrogers@worldnet.att.net>]

"Wojtek Narczynski" <wojtek@power.com.pl> wrote in message
news:5ad0dd8a.0301271851.7c907f60@posting.google.com...
> "James S. Rogers" <jimmaureenrogers@worldnet.att.net> wrote in message
news:<PriZ9.6187$rq4.561874@bgtnsc05-news.ops.worldnet.att.net>...
>
> > If you want to use a more general access to string try using an access
> > to an unbounded string. See the following:
>
> Uhm, I switched to String from Stream_Element_Array because the old
> GNAT code example used it. In my project there is something like this:
>
>  subtype Content_Length_Type is
>     Stream_Element_Count range 0 .. 2 ** 16 - 1;
>  subtype Padding_Length_Type
>     is Stream_Element_Count range 0 .. 2 ** 8 - 1;
>
>  type Content_Type
>     ( Content_Length : Content_Length_Type;
>     Padding_Length : Padding_Length_Type )
>  is record
>    Content : aliased Stream_Element_Array( 1..Content_Length );
>    case Padding_Length is
>       when 0 => null;
>       when others => Padding : Stream_Element_Array( 1..Padding_Length
> );
>    end case;
>  end record;
>
>
> First I read a header with Content_Length and Padding_Length from
> socket, then I use declare to read the actual content in another
> syscall.
>
> Then I wanted to pass the access to Content to a function that accepts
> access Stream_Element_Array as its parameter. Looks like this cannot
> be done though.

Why are you choosing to pass an access to a Stream_Element_Array
instead of just the Stream_Element_Array? Avoiding the use of an
access type would also eliminate the problem. Remember that any
parameter, even an IN parameter can be passed by reference by the
compiler. In fact, an array object is most frequently passed by reference.

>
> And in general I find the inablility to declare access type subtypes
> in parallel with the subtypes for the designated type obstructive.

It appears that you are thinking in C while programming in Ada.

Jim Rogers