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Re: Integer promotions, conversions, coercions and templates :(

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From Ian Collins <ian-news@hotmail.com>
Newsgroups comp.lang.c++
Subject Re: Integer promotions, conversions, coercions and templates :(
Date Fri, 10 Jun 2011 10:40:41 +1200
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On 06/10/11 10:15 AM, MikeP wrote:
> Ian Collins wrote:
>
>> Anyway, if you were using a
>> macro you would have to have a parameter for the suffix.
>
> Yes, as I wanted with the template (for lack of any other way), but
> templates won't allow it.

Because they don't require it.  The type is known.

> I thought I had it down for awhile, but I
> hadn't yet called any of the member functions of the template class so
> the code genrator did not generate code for those member functions and
> everything seemed "way-kewl", until I wrote the test and started calling
> the functions and then the compiler complained. So, I can do what I
> wanted to do with the macro but not with the template, and if I do it in
> "super macro" style, it may be a better solution than jumping through
> hoops with the template "deficiency" (TBD).

Hoops?  What could be simpler than

template <typename T>
bool CheckBit( T mask, unsigned n)
{
   assert( n < std::numeric_limits<T>::digits );

   return (mask & (T(1) << (n-1)));
}

bool result = CheckBit( 42ull, 4 );

?
>> In a
>> template you have the type and as Öö Tiib pointed out else-thread,
>> you only need one template parameter, which the compiler can deduce.
>
> It's not worth pulling in the header for that. All I'm trying to do is
> avoid code duplication for 4 classes, but templates are fighting me. It
> can be done, of course, as shown above, it's just not elegant is all.

Pulling in a header?  isn't that what they are there for?

-- 
Ian Collins

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Thread

Integer promotions, conversions, coercions and templates :( "MikeP" <mp011011@some.org> - 2011-06-08 17:09 -0500
  Re: Integer promotions, conversions, coercions and templates :( Ian Collins <ian-news@hotmail.com> - 2011-06-09 10:22 +1200
    Re: Integer promotions, conversions, coercions and templates :( "MikeP" <mp011011@some.org> - 2011-06-08 17:49 -0500
    Re: Integer promotions, conversions, coercions and templates :( "MikeP" <mp011011@some.org> - 2011-06-08 19:13 -0500
      Re: Integer promotions, conversions, coercions and templates :( Ian Collins <ian-news@hotmail.com> - 2011-06-09 14:32 +1200
        Re: Integer promotions, conversions, coercions and templates :( "MikeP" <mp011011@some.org> - 2011-06-09 07:30 -0500
          Re: Integer promotions, conversions, coercions and templates :( Öö Tiib <ootiib@hot.ee> - 2011-06-09 06:18 -0700
            Re: Integer promotions, conversions, coercions and templates :( "MikeP" <mp011011@some.org> - 2011-06-09 08:45 -0500
              Re: Integer promotions, conversions, coercions and templates :( Öö Tiib <ootiib@hot.ee> - 2011-06-09 06:51 -0700
                Re: Integer promotions, conversions, coercions and templates :( "MikeP" <mp011011@some.org> - 2011-06-09 13:44 -0500
          Re: Integer promotions, conversions, coercions and templates :( Ian Collins <ian-news@hotmail.com> - 2011-06-10 07:37 +1200
            Re: Integer promotions, conversions, coercions and templates :( "MikeP" <mp011011@some.org> - 2011-06-09 15:11 -0500
              Re: Integer promotions, conversions, coercions and templates :( Ian Collins <ian-news@hotmail.com> - 2011-06-10 09:09 +1200
                Re: Integer promotions, conversions, coercions and templates :( "MikeP" <mp011011@some.org> - 2011-06-09 17:15 -0500
                Re: Integer promotions, conversions, coercions and templates :( Ian Collins <ian-news@hotmail.com> - 2011-06-10 10:40 +1200
                Re: Integer promotions, conversions, coercions and templates :( "MikeP" <mp011011@some.org> - 2011-06-10 05:07 -0500
                Re: Integer promotions, conversions, coercions and templates :( Öö Tiib <ootiib@hot.ee> - 2011-06-10 03:14 -0700
                Re: Integer promotions, conversions, coercions and templates :( Öö Tiib <ootiib@hot.ee> - 2011-06-10 03:19 -0700
                Re: Integer promotions, conversions, coercions and templates :( "MikeP" <mp011011@some.org> - 2011-06-10 06:08 -0500
                Re: Integer promotions, conversions, coercions and templates :( Öö Tiib <ootiib@hot.ee> - 2011-06-10 04:32 -0700
                Re: Integer promotions, conversions, coercions and templates :( "MikeP" <mp011011@some.org> - 2011-06-10 07:14 -0500
                Re: Integer promotions, conversions, coercions and templates :( Öö Tiib <ootiib@hot.ee> - 2011-06-10 05:27 -0700
                Re: Integer promotions, conversions, coercions and templates :( "MikeP" <mp011011@some.org> - 2011-06-10 07:35 -0500
                Re: Integer promotions, conversions, coercions and templates :( Öö Tiib <ootiib@hot.ee> - 2011-06-10 06:47 -0700
                Re: Integer promotions, conversions, coercions and templates :( "MikeP" <mp011011@some.org> - 2011-06-10 06:18 -0500
                Re: Integer promotions, conversions, coercions and templates :( Ian Collins <ian-news@hotmail.com> - 2011-06-11 08:08 +1200
                Re: Integer promotions, conversions, coercions and templates :( "MikeP" <mp011011@some.org> - 2011-06-10 18:41 -0500
    Re: Integer promotions, conversions, coercions and templates :( "MikeP" <mp011011@some.org> - 2011-06-10 08:11 -0500
  Re: Integer promotions, conversions, coercions and templates :( Öö Tiib <ootiib@hot.ee> - 2011-06-09 06:28 -0700
    Re: Integer promotions, conversions, coercions and templates :( "MikeP" <mp011011@some.org> - 2011-06-09 08:50 -0500
  Re: Integer promotions, conversions, coercions and templates :( (Summary so far) "MikeP" <mp011011@some.org> - 2011-06-10 08:40 -0500
    Re: Integer promotions, conversions, coercions and templates :( (Summary so far) Öö Tiib <ootiib@hot.ee> - 2011-06-10 07:14 -0700
      Re: Integer promotions, conversions, coercions and templates :( (Summary so far) "MikeP" <mp011011@some.org> - 2011-06-10 09:17 -0500
    Re: Integer promotions, conversions, coercions and templates :( (Summary so far)(Corrections and more) "MikeP" <mp011011@some.org> - 2011-06-10 09:14 -0500
      Re: Integer promotions, conversions, coercions and templates :( (Results: Generated Code) "MikeP" <mp011011@some.org> - 2011-06-10 12:43 -0500
  Re: Integer promotions, conversions, coercions and templates :( (Conclusion) "MikeP" <mp011011@some.org> - 2011-06-14 18:35 -0500
    Re: Integer promotions, conversions, coercions and templates :( (Conclusion) Ian Collins <ian-news@hotmail.com> - 2011-06-15 12:51 +1200
      Re: Integer promotions, conversions, coercions and templates :( (Conclusion) "MikeP" <mp011011@some.org> - 2011-06-15 08:45 -0500
    Re: Integer promotions, conversions, coercions and templates :( (Conclusion) Michael DOUBEZ <michael.doubez@free.fr> - 2011-06-15 03:33 -0700
      Re: Integer promotions, conversions, coercions and templates :( (Conclusion) "MikeP" <mp011011@some.org> - 2011-06-15 09:17 -0500
        Re: Integer promotions, conversions, coercions and templates :( (Conclusion) Michael DOUBEZ <michael.doubez@free.fr> - 2011-06-16 04:17 -0700
          Re: Integer promotions, conversions, coercions and templates :( (Conclusion) "MikeP" <mp011011@some.org> - 2011-06-16 09:45 -0500
            Re: Integer promotions, conversions, coercions and templates :( (Conclusion) Michael DOUBEZ <michael.doubez@free.fr> - 2011-06-17 01:56 -0700
              Re: Integer promotions, conversions, coercions and templates :( (Conclusion) "MikeP" <mp011011@some.org> - 2011-06-17 07:58 -0500
                Re: Integer promotions, conversions, coercions and templates :( (Conclusion) Michael DOUBEZ <michael.doubez@free.fr> - 2011-06-17 06:54 -0700
                Re: Integer promotions, conversions, coercions and templates :( (Conclusion) "MikeP" <mp011011@some.org> - 2011-06-17 09:19 -0500
              Re: Integer promotions, conversions, coercions and templates :( (Conclusion) "MikeP" <mp011011@some.org> - 2011-06-17 08:17 -0500
                Re: Integer promotions, conversions, coercions and templates :( (Conclusion) Michael DOUBEZ <michael.doubez@free.fr> - 2011-06-17 07:33 -0700
                Re: Integer promotions, conversions, coercions and templates :( (Conclusion) "MikeP" <mp011011@some.org> - 2011-06-17 09:49 -0500

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