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From: "David Botton" <David@Botton.com>
Newsgroups: comp.lang.ada
Subject: Re: Variable length raw-byte data
Date: Wed, 13 Dec 2000 10:48:31 -0500
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Date: 2000-12-13T10:48:31-05:00

Since Byte_List is unconstrained is there not a potential for problem here
with additional data associated with the type for bounds?

> type Byte_List is array (Positive range <>) of Unsigned_8;

Would this be a better solution:

C_Thing (Length, Pointer)

declare
    type Byte_List is array (1 .. Length) of Unsigned_8;
    Thing : Byte_List;
    for Thing'Address use Pointer;

begin
   ...
end;


I frequently code the above as:

C_Thing (Length, Pointer)

declare
    type Byte_List is array (1 .. Length) of Unsigned_8;
    type Pointer_To_Byte_List is access all Byte_List;

    function To_Pointer_To_Byte_List is
       new Ada.Unchecked_Conversion (System.Address, Pointer_To_Byte_List);

    Thing : Pointer_To_Byte_List := To_Pointer_To_Byte_List
(Pointer'Address);
begin
 ...
end;

Is there a reason that using the for Thing'Address would be a better
solution then the second method?

David Botton