On Sat, 6 Apr 2013, Dmitry A. Kazakov wrote:

>> The same for conversions between Integer and Float.
>
> Nope. You cannot convert house number to outdoor temperature.

So what? Neither can I convert my zip code to my birth year (both 
Positive) or the outdoor temperature to speed of light. ;-)

Ada allows to define types such as, Apples and Oranges, or, say Speed and 
Temperature. But this has nothing to do with the underlying mathematical 
struture of each of these types.

Actually, mixing integers and float (or integers and fixed-point numbers) 
is not that uncommon. The maximum speed for a vehicle, say, a train at a 
certain part of the track, is, most likely, an integer, while the speed 
the sensors measure isn't an integer. So you have something like the 
following code:

   Current_Speed : Speed;
   Max_Speed     : Integer_Speed;
   Safety_Margin : constant Speed := ...
   ...
   if Current_Speed > Speed(Max_Speed) then
     Display_Warning(Speed_Warning);
     Play_Alarm_Sound;
     if Current_Speed < (Speed(Max_Speed) + Safety_Margin) then
       Perform_Emergency_Break;
     end_if:
   end_if;

Here, you need the to convert Max_Speed to Speed, even though the two 
types Speed and Integer_Speed have the same semantic.

I don't think we'll agree on this issue, but I fail to see any significant 
distinction between the class of arithmetic types and string types.



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