Re: using the 'use at' feature inside a record?

[Per Sandberg <per.sandberg@bredband.net>]

Well there are always unchecked unions:
    "ARM B.3.3 Pragma Unchecked_Union"
---------------------------
    type foo (dummy : Integer := 0) is record
       case dummy is
       when 1 =>
          as_integer              : integer;
       when 2 =>
          as_float                : Short_Float;
       when 3 =>
          as_String               : String (1 .. 4);
       when others =>
          as_Stream_Element_Array : Ada.Streams.Stream_Element_Array (1 
.. 4);
       end case;
    end record;
    pragma unchecked_Union(foo);
---------------------------

The above construct will is an exact equivalent of C's unions.

/Per


PForan wrote:
> Hi all,
> 
> I have a question about the "use at" feature and how it can be used
> inside a record to simulate C's unions. I often have an array of
> bytes, as well as a string which is "use at"'ed on top of the byte
> buffer, very useful as I can play with the data in any way I choose.
> i.e.
> 
> byte_buf: array(1..100) of unsigned_8;
> str_buf: string(1..100);
> for str_buf use at byte_buf'address;
> 
> Is it possible to have something like this within a record?
> 
> TIA,
> Phil