Re: passing parametars as determinants

[Shark8 <OneWingedShark@gmail.com>]

On 10/22/2014 5:55 AM, compguy45@gmail.com wrote:
> task type myTaskType (a: Integer; b: Integer; c: access myOtherType);
>
>
> This is where i create tasks.....
>
>
> := new myTaskType(a=> i, b => j,c =>  access'myOtherType);
>
> I get compiler error "reserved word "access" cannot be used as identifier"
>

Here's an example of using an access discriminant in a task-type:

With
Ada.Text_IO;

procedure Test is

    -- This is the type for the data to be passed to the task-type.
    Type Info is array (positive range <>) of Integer;

    -- The task-type's public interface.
    Task Type Print_Task( Info_Param : not null access Info ) is
       entry Print  ( Index : in Positive );
       entry Done;
    end Print_Task;


    -- The body of the task-type.
    Task body Print_Task is
       subtype Data_Range is Positive range Info_Param'Range;
       Procedure Put( Index : Data_Range ) is
       begin
          Ada.Text_IO.Put_Line("Data(" & Integer'Image(Index) & " ) ->"
                               & ASCII.HT & Integer'Image(Info_Param(Index))
                              );
       end Put;
       -- Variable indicating if we're finished.
       Finished : Boolean := False;
    begin
       loop
          -- Select lets us accept things non-sequentially; A or B,
          -- rather than A then B.
          select
             accept Done  do
                -- We're free to exit the task.
                Finished:= True;
             end Done;
          or
             accept Print (Index : in Positive) do
                -- If the input is outside the range of the data, we print
                -- an error-message, otherwise we desplay the indicated 
data.
                if Index not in Data_Range then
                   Ada.Text_IO.Put_Line("[ERROR] Index out of range.");
                else
                   Put(Index);
                end if;
             end Print;
          end select;
          -- When Finished is flagged, we break out of the loop.
          exit when Finished;
       end loop;
       Ada.Text_IO.Put_Line("Goodbye.");
    end Print_Task;


    -- This is the actual object of data we will pass to the task.
    Data : aliased Info:= (8,3,-1,2);

    -- The actual task.
    SOME_TASK : Print_Task( Info_Param => Data'Access );



    use Ada.Text_IO;
begin
    SOME_TASK.Print(3);
    SOME_TASK.Done;
--     Put_Line( "P(24) =" & P(K'Last)'Img );
end Test;