Re: Bitwise XOR?

["Steve" <nospam_steved94@comcast.net>]

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"Adrian Knoth" <adi@thur.de> wrote in message
news:slrnbnnohq.26h.adi@ppc201.mipool.uni-jena.de...
> David N. Maez <sellout@dharmadevil.com> wrote:
>
> >   x : integer;
> >   y : integer;
> >   x := x xor y;
>
> > What am I missing?
>
> There is no XOR defined for anything else than bits. You'll need
> to mask the bits and recombine the result.
>

Not true.

Ada 95 permits using XOR on modular types.
If you want to XOR between integers, convert the integer to a modular type,
do the XOR,
then convert the result back.  The following (tested) routine does exactly
this.

  function "xor"(Left,Right : in Integer) return Integer is
    pragma inline("xor");
    type Int_As_Mod is mod 2 ** Integer'size;
    function To_Mod is new Ada.Unchecked_Conversion( Integer, Int_As_Mod );
    function To_Int is new Ada.Unchecked_Conversion( Int_As_Mod, Integer );
  begin
    return To_Int( To_Mod(Left) XOR To_Mod(Right) );
  end "xor";

Steve
(The Duck)

[excessively complicated untested example deleted]
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