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Re: enum type in template declaration

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Il 07/12/19 10:53, saturnman2008@gmail.com ha scritto:
> 在 2019年12月6日星期五 UTC+8上午6:21:05，Soviet_Mario写道：
>> since what version of standard, if any, an ENUM type can be
>> an argument of a template ?
>>
>> sth like
>>
>> enum class RestrictedValues { A = 1, B = 2, C = 4, D = 8 };
>>
>>
>> template <RestrictedValues ttVal> class SizedField
>> {
>    public:
>   static constexpr int aSize = static_cast<int>(ttVal);
>> private:
> 
>> unsigned char zzArray [aSize];


Yes it was a slight of mine to not have converted an enum to 
int explicitely.
But the main question was not about that.
Anyway they have just reassured me that the compiler checks 
for invalid non-forced cast in the reverse sense (from a 
generic integer to the enum) in the specialization of an 
instance. That was the source of my concern.

The forced manual cast did not worry me, I try not to shoot 
in my foot :)

>>
>>
>> public:
>>
>> etc etc
>>
>> }
>>
>>
>> or if the syntax is wrong, how to workaround ?
>>
>> The goal is to have a template depending on a restricted
>> well defined, and known at compile time, set of integral values
>>
>>
>>
>> enum RestrictedValues { A = 1, B = 2, C = 4, D = 8 };
> 
> 
> template <RestrictedValues ttVal> class SizedField
> {
> private:
> unsigned char zzArray [ttVal];
> 
> 
> public:
> 
> etc etc
> 
> }
>>
>>
>>
>> -- 
>> 1) Resistere, resistere, resistere.
>> 2) Se tutti pagano le tasse, le tasse le pagano tutti
>> Soviet_Mario - (aka Gatto_Vizzato)
> 
> 
> If my modification fits your requirement?
> 


-- 
1) Resistere, resistere, resistere.
2) Se tutti pagano le tasse, le tasse le pagano tutti
Soviet_Mario - (aka Gatto_Vizzato)

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enum type in template declaration Soviet_Mario <SovietMario@CCCP.MIR> - 2019-12-05 23:20 +0100
  Re: enum type in template declaration James Kuyper <jameskuyper@alumni.caltech.edu> - 2019-12-05 22:39 -0500
    Re: enum type in template declaration Soviet_Mario <SovietMario@CCCP.MIR> - 2019-12-06 13:15 +0100
      Re: enum type in template declaration Paavo Helde <myfirstname@osa.pri.ee> - 2019-12-06 14:42 +0200
        Re: enum type in template declaration Soviet_Mario <SovietMario@CCCP.MIR> - 2019-12-06 17:20 +0100
          Re: enum type in template declaration Paavo Helde <myfirstname@osa.pri.ee> - 2019-12-06 20:29 +0200
            Re: enum type in template declaration Soviet_Mario <SovietMario@CCCP.MIR> - 2019-12-06 22:42 +0100
              Re: enum type in template declaration Paavo Helde <myfirstname@osa.pri.ee> - 2019-12-07 00:51 +0200
                Re: enum type in template declaration Soviet_Mario <SovietMario@CCCP.MIR> - 2019-12-07 18:54 +0100
      Re: enum type in template declaration Öö Tiib <ootiib@hot.ee> - 2019-12-06 06:00 -0800
      Re: enum type in template declaration James Kuyper <jameskuyper@alumni.caltech.edu> - 2019-12-06 09:56 -0500
      Re: enum type in template declaration Manfred <noname@add.invalid> - 2019-12-06 15:56 +0100
  Re: enum type in template declaration Soviet_Mario <SovietMario@CCCP.MIR> - 2019-12-06 18:43 +0100
  Re: enum type in template declaration saturnman2008@gmail.com - 2019-12-07 01:53 -0800
    Re: enum type in template declaration Soviet_Mario <SovietMario@CCCP.MIR> - 2019-12-07 18:57 +0100

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