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In article <3dde25a1$1@newsgroups.borland.com>, Stephen Froude says...

> This is strange.  If I run the following code, the for loop breaks on 233.  
> Why does this happen???  I'm using Delphi 6 Ent
 
> procedure TForm1.Button1Click(Sender: TObject);
> const
>   STATUS_NEW: Integer = 100;
>   STATUS_CANCELLED: Integer = 1000;
> var
>   iLoop, iStatus: Integer;
> begin
>   for iLoop:= STATUS_NEW to STATUS_CANCELLED do
>   begin
>     iStatus := iLoop;
>     if not (iStatus in [STATUS_NEW..STATUS_CANCELLED]) then
>     begin
>       ShowMessage('Failed on ' + IntToStr(iStatus));
>       Break;
>     end;
>   end;
> end;

Because sets like [STATUS_NEW..STATUS_CANCELLED] can only contain values 
0..255. If you had range checking on, you would get a range check error. 
Now you simply get a cut off version, i.e. only the lower byte of 1000, 
which is 232.

Reminder: ALWAYS test (and IMHO deploy as well) with Range and Overflow 
Checking on! This will catch a lot of otherwise weird errors in your 
code.

"In" is only useful for values in the range 0..255. Otherwise you should 
use:

  if (iStatus >= STATUS_NEW) and (iStatus <= STATUS_CANCELLED) then

-- 
Rudy Velthuis (TeamB)

"We should leave our minds open, but not so open that our brains 
 fall out." - Alan Ross Anderson