Re: Operators Questions

[mheaney@ni.net (Matthew Heaney)]

In article <3275D478.5952@eurocontrol.fr>, Richard Irvine
<Richard.Irvine@eurocontrol.fr> wrote:

Put this on my wish list for the next revision of the language: the ability
to overload the membership operator "in".  That way I can say

generic
   type T is private;
package Sets is

   type Set is private;

   function "in" (Left : T, Right : Set) return Boolean;
...
end;

package Integer_Sets is new Sets (Integer);
subtype Integer_Set is Integer_Sets.Set;
use Integer_Sets;

   The_Set : Integer_Set;
begin
   ...
   if 4 in The_Set then
      ...


I think that that's much hipper than

   if Is_Member_Of (The_Set, Item => 4) then
      ...

But of course your mileage may vary.  

Language designers: any reason overloading of "in" is too difficult for
inclusion in the language?  Why can't you do this already?  This exclusion
of the ability to overload "in" seems rather odd and unexpected.

--------------------------------------------------------------------
Matthew Heaney
Software Development Consultant
mheaney@ni.net
(818) 985-1271