Re: Timing Block of GNAT code in milliseconds

[Simon Wright <simon@pushface.org>]

"markp" <markwork66@yahoo.com> writes:

> Thanks for your response:
> 
> I tried this and got some errors. Hereis what my code looks like
> 
>    My_Time    : Ada.Calendar.Time;
>    Result        : Ada.Calendar.Time;
> 
>   My_Time := Ada.Calendar.Clock;
>   Result  := (Ada.Calendar.Clock - My_Time)/1000;
> 
> The error I get is :
> 
> Expected private type Ada.Calendar.Time
> Expected type Standard Duration
> 
> on the piece of code (Ada.Calendar.Clock - My_Time).

You need to say

   use type Ada.Calendar.Time;

in a declarative region (I usually put this just before the 'begin').

That gives you access to the operation "-" taking two parameters of
type Ada.Calendar.Time and returning a Duration; your Result should be
of type Duration (a Time corresponds to the wall-clock time, whereas
Duration is an interval).

The error message you got is reasonable; if you subtract "4 Jan 2004"
from "4 Jan 2005", you get "1 year" not "1 Jan 1971"!

> Lastly,
> 
> How would I print out Result?

Did you say what compiler/platform you're using?

On any platform you can say (eg)

  Ada.Text_IO.Put_Line ("Result is " & Duration'Image (Result));

GNAT has the non-portable extension 'Img so you can say

  Ada.Text_IO.Put_Line ("Result is " & Result'Img);

-- 
Simon Wright                               100% Ada, no bugs.