Re: Nested Task Entry Question

[Shark8 <onewingedshark@gmail.com>]

On Tuesday, April 24, 2018 at 10:57:29 AM UTC-6, NiGHTS wrote:
> I have two tasks: Task P and Task C. Task P creates Task C, but Task C must call entries into Task P. 
> 
> I can't seem to figure out how to make an entry on a parent task executable by a child task.
> 
> I am eternally grateful for your assistance! Thank you!

    Task Type Parent is
	Entry Start;
	Entry Child_Call( Value : Natural );
	Entry Stop;
    End Parent;
    
    Task Type Child( P : not null access Parent ) is
    End Child;
    
    Task Body Child is
    Begin
	Ada.Text_IO.Put_Line( "Inside Child; Setting Parent value.");
	P.Child_Call( 23 );
    End Child;
    
    Task Body Parent is
	Internal : Natural := 77;
    Begin
	accept Start  do
	    Ada.Text_IO.Put_Line( "Starting Parent (Value:" &
			     Natural'Image(Internal) & " )." );
	end Start;
	accept Child_Call (Value : in Natural) do
	    Ada.Text_IO.Put_Line( "Call from child." );
	    Internal := Value;
	end Child_Call;
	accept Stop  do
	    Ada.Text_IO.Put_Line( "Stopping Parent (Value:" &
			     Natural'Image(Internal) & " )." );
	end Stop;
    End Parent;

--...
    Parent_Task.Start;
    -- Hidden Child call happens after Start finishes, due to being queued on entry.
    Parent_Task.Stop;

----------------
Also, note that the putline happens *BEFORE* the output of the Parent-task; this is because the queuing on the entry happens, due to the parent having to wait for the START entry.