Re: What is the best method for transmitting objects/tagged records?

[Shark8 <onewingedshark@gmail.com>]

On Jun 8, 7:49 pm, "Randy Brukardt" <ra...@rrsoftware.com> wrote:
> "Shark8" <onewingedsh...@gmail.com> wrote in message
>
>
> >(WITH-ing Ada.Streams is fine because it is a Pure package.)
>
> Right, but you don't need to use Ada.Tags (or anything tags) in order to
> stream tagged types. Just use the provided T'Class'Input and T'Class'Output
> attributes. For those to have portable results, you need to specify your
> external tag values for your tagged types (we previously discussed that).
>
>                                             Randy.

Oh!
{ I assume you mean something like Function Parse( Input :
stream_type ) Return Hierarchy_Parent'Class; no? }

So I was right in that I need to redefine my interfaces.

I currently have a task; which cannot return values as a function
would, and therefore cannot be used to
directly initialize an class-wide variable.

What I'm going to have to do then, is 'hide' the task in the body;
something like this:
Package Parser is

Task Type Parser_Task is
 -- Get Text and get_Token do essentially the same thing; in my setup
 -- I would like to try the tokenizing on client- and server-side
 -- to compare the efficiencies of the two.
 --
 -- Sorry about the poor naming & invalid code; I'm just typing up
psudeocode.
 Entry Get_Token(Token_Stream : Access stream); -- reads a token
 Entry Get_Text( Text_Stream : access stream ); -- read text-stream
 Entry Get_Tag(  The_Tag : Out Tag  );
 Entry Get_Object( The_Object : Out Object'Class );
End Parser_Task;

[...]
The_Parser : Parser_Task;
[...]

Function Pars( Input : Access Ada.Streams.Stream'Class ) Return
Object'Class is
 T : Tag;
begin

The_Parser.Get_Text( Input );
The_Parser.Get_Tag( T );

-- use dispatching construction
Declare
 This_Object : Object'Class:= Dispatch( T );
Begin
 The_Parser.Get_Object( This_Object );
 Return This_Object;
End;

end Parse;

End parser;