Re: Abortable Timed Action

[Anh Vo <anhvofrcaus@gmail.com>]

On Wednesday, December 30, 2015 at 8:15:15 PM UTC-8, T.G. wrote:
> Hello everyone. Is there a better way to implement a timed action?
> I've tried the following :
> 
>    task type Timed_Action_Task is
>      entry Exec_After (T : Duration);
>      entry Cancel;
>      entry Finish;
>    end Timed_Action_Task;
> 
>    task body Timed_Action_Task is
>       Timeout : Duration;
>    begin
>       loop
>          select
>             accept Exec_After (T : Duration) do
>                Timeout := T;
>             end Exec_After;
>             select
>                accept Cancel;
>             or
>                delay Timeout;
>                Do_Something;
>             end select;
>          or
>             accept Finish;
>             exit;
>          end select;
>       end loop;
>    end Timed_Action_Task;
> 
> and then later something like
> 
>   Timed_Action.Exec_After (5.0);
>   ...
>   if Something_Changed then
>      Timed_Action.Cancel;
>   end if;
> 
> it works, I've also tried,
> 
>    task body Timed_Action_Task is
>       Timeout  : Duration := Duration'Last;
>    begin
>       loop
>          select
>             accept Exec_After (T : Duration) do
>                Timeout := T;
>             end Exec_After;
>          or
>             accept Cancel;
>             Timeout := Duration'Last;
>          or
>             accept Finish;
>             exit;
>          or
>             delay Timeout;
>             Do_Something;
>             Timeout := Duration'Last;
>          end select;
>       end loop;
>    end Timed_Action_Task;
> 
> any other options?

Look like your code worked like a timer. Was it your intention to create a timer?

Anh Vo