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Re: What is the good of new way of coding?

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On Sat, 17 Sep 2022 18:03:37 +0200
Bonita Montero <Bonita.Montero@gmail.com> wrote:
>Am 17.09.2022 um 17:59 schrieb Muttley@dastardlyhq.com:
>> On Sat, 17 Sep 2022 17:31:19 +0200
>> Bonita Montero <Bonita.Montero@gmail.com> wrote:
>>> Am 17.09.2022 um 16:50 schrieb Muttley@dastardlyhq.com:
>>>> On Sat, 17 Sep 2022 15:03:25 +0200
>>>> Bonita Montero <Bonita.Montero@gmail.com> wrote:
>>>>> Am 17.09.2022 um 14:46 schrieb wij:
>>>>>> I did not update my C++ understanding (probable since C++11) to find out
>I
>>>>>> cannot understand what the codes are about !!!
>>>>>>
>>>>>> --- frorm https://groups.google.com/g/comp.lang.c++/c/2ebc6ifoPr4
>>>>>> #include <iostream>
>>>>>> #include <utility>
>>>>>>
>>>>>> using namespace std;
>>>>>>
>>>>>> int main()
>>>>>> {
>>>>>> auto pow = []<unsigned P>( double b, integral_constant<unsigned, P> )
>>>>>> -> double
>>>>>> {
>>>>>> auto unroll = [&]<size_t ... Indices>( index_sequence<Indices ...> )
>>>>>> -> double
>>>>>> {
>>>>>> return ((Indices, b) * ...);
>>>>>> };
>>>>>> if constexpr( P )
>>>>>> return unroll( make_index_sequence<P>() );
>>>>>> else
>>>>>> return b;
>>>>>> };
>>>>>> cout << pow( 2.0, integral_constant<unsigned, 10'000>() ) << endl;
>>>>>> }
>>>>>> ------
>>>>>>
>>>>>> Question1: What would the code look like if using C++2006 for the above
>>>>> 'program'?
>>>>>
>>>>> It's not possible to write that before C++20.
>>>>
>>>> Really? So it outputs some special assembler reserved for C++20 does it?
>>>>
>>>
>>> No, you can't unroll variable.
>> 
>> I'm pretty sure the same functionality could be achieved in older C++ or
>> even C albeit with more lines of code.
>> 
>
>Show me.
>

I don't have a c++ 20 compiler so I can't see what it does and I have better
things to do on a saturday than run it in my head.

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What is the good of new way of coding? wij <wyniijj2@gmail.com> - 2022-09-17 05:46 -0700
  Re: What is the good of new way of coding? Bonita Montero <Bonita.Montero@gmail.com> - 2022-09-17 15:03 +0200
    Re: What is the good of new way of coding? Muttley@dastardlyhq.com - 2022-09-17 14:50 +0000
      Re: What is the good of new way of coding? Bonita Montero <Bonita.Montero@gmail.com> - 2022-09-17 17:31 +0200
        Re: What is the good of new way of coding? Muttley@dastardlyhq.com - 2022-09-17 15:59 +0000
          Re: What is the good of new way of coding? Bonita Montero <Bonita.Montero@gmail.com> - 2022-09-17 18:03 +0200
            Re: What is the good of new way of coding? Muttley@dastardlyhq.com - 2022-09-17 16:13 +0000
              Re: What is the good of new way of coding? Bonita Montero <Bonita.Montero@gmail.com> - 2022-09-17 18:34 +0200
                Re: What is the good of new way of coding? "Alf P. Steinbach" <alf.p.steinbach@gmail.com> - 2022-09-17 19:55 +0200
                Re: What is the good of new way of coding? "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2022-09-17 12:03 -0700
                Re: What is the good of new way of coding? Bonita Montero <Bonita.Montero@gmail.com> - 2022-09-18 16:21 +0200
                Re: What is the good of new way of coding? Muttley@dastardlyhq.com - 2022-09-19 08:30 +0000
                Re: What is the good of new way of coding? Bonita Montero <Bonita.Montero@gmail.com> - 2022-09-19 10:37 +0200
                Re: What is the good of new way of coding? Muttley@dastardlyhq.com - 2022-09-19 08:54 +0000
                Re: What is the good of new way of coding? Bonita Montero <Bonita.Montero@gmail.com> - 2022-09-19 11:13 +0200
  Re: What is the good of new way of coding? Bonita Montero <Bonita.Montero@gmail.com> - 2022-09-17 15:23 +0200
    Re: What is the good of new way of coding? Bonita Montero <Bonita.Montero@gmail.com> - 2022-09-17 15:38 +0200
  Re: What is the good of new way of coding? Andreas Kempe <kempe@lysator.liu.se> - 2022-09-17 14:37 +0000
    Re: What is the good of new way of coding? Bonita Montero <Bonita.Montero@gmail.com> - 2022-09-17 16:40 +0200
      Re: What is the good of new way of coding? Andreas Kempe <kempe@lysator.liu.se> - 2022-09-17 20:52 +0000
        Re: What is the good of new way of coding? Mr Flibble <flibble@reddwarf.jmc.corp> - 2022-09-17 22:18 +0100
          Re: What is the good of new way of coding? Mr Flibble <flibble@reddwarf.jmc.corp> - 2022-09-17 22:21 +0100
            Re: What is the good of new way of coding? Andreas Kempe <kempe@lysator.liu.se> - 2022-09-17 21:31 +0000
  Re: What is the good of new way of coding? Muttley@dastardlyhq.com - 2022-09-17 14:52 +0000
    Re: What is the good of new way of coding? Bonita Montero <Bonita.Montero@gmail.com> - 2022-09-17 17:32 +0200

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