How can I get the type in a C++17 fold function?

From	Muttley@dastardlyhq.com
Newsgroups	comp.lang.c++
Subject	How can I get the type in a C++17 fold function?
Date	2022-12-08 09:48 +0000
Organization	Aioe.org NNTP Server
Message-ID	<tmsbtq$fp6$1@gioia.aioe.org> (permalink)

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eg:

template<typename... T>
auto sum(T&&... args)
{
        if (typeid(T) == typeid(string)) { do something }
        return (args + ...);
}

However doing typeid on T gives 

error: expression contains unexpanded parameter pack 'T'

in clang.

Is there a way to get the type inside the function?

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Thread

How can I get the type in a C++17 fold function? Muttley@dastardlyhq.com - 2022-12-08 09:48 +0000
  Re: How can I get the type in a C++17 fold function? Juha Nieminen <nospam@thanks.invalid> - 2022-12-08 12:18 +0000
    Re: How can I get the type in a C++17 fold function? Muttley@dastardlyhq.com - 2022-12-08 15:41 +0000
      Re: How can I get the type in a C++17 fold function? Juha Nieminen <nospam@thanks.invalid> - 2022-12-09 12:57 +0000
  Re: How can I get the type in a C++17 fold function? Öö Tiib <ootiib@hot.ee> - 2022-12-08 04:45 -0800
    Re: How can I get the type in a C++17 fold function? Muttley@dastardlyhq.com - 2022-12-08 15:45 +0000
      Re: How can I get the type in a C++17 fold function? Öö Tiib <ootiib@hot.ee> - 2022-12-08 13:59 -0800
  Re: How can I get the type in a C++17 fold function? Vir Campestris <vir.campestris@invalid.invalid> - 2022-12-14 10:42 +0000
  Re: How can I get the type in a C++17 fold function? Bonita Montero <Bonita.Montero@gmail.com> - 2022-12-14 18:02 +0100
    Re: How can I get the type in a C++17 fold function? Muttley@dastardlyhq.com - 2022-12-14 17:17 +0000
      Re: How can I get the type in a C++17 fold function? Bonita Montero <Bonita.Montero@gmail.com> - 2022-12-14 18:23 +0100
  Re: How can I get the type in a C++17 fold function? Bonita Montero <Bonita.Montero@gmail.com> - 2022-12-15 17:59 +0100
    Re: How can I get the type in a C++17 fold function? Muttley@dastardlyhq.com - 2022-12-15 17:20 +0000
      Re: How can I get the type in a C++17 fold function? Bonita Montero <Bonita.Montero@gmail.com> - 2022-12-15 18:37 +0100
    Re: How can I get the type in a C++17 fold function? Bonita Montero <Bonita.Montero@gmail.com> - 2022-12-16 05:26 +0100
      Re: How can I get the type in a C++17 fold function? Bonita Montero <Bonita.Montero@gmail.com> - 2022-12-16 05:41 +0100
        Re: How can I get the type in a C++17 fold function? scott@slp53.sl.home (Scott Lurndal) - 2022-12-16 15:17 +0000
          Re: How can I get the type in a C++17 fold function? Bonita Montero <Bonita.Montero@gmail.com> - 2022-12-16 18:22 +0100
            Re: How can I get the type in a C++17 fold function? scott@slp53.sl.home (Scott Lurndal) - 2022-12-16 17:42 +0000
              Re: How can I get the type in a C++17 fold function? Bonita Montero <Bonita.Montero@gmail.com> - 2022-12-16 19:20 +0100
          Re: How can I get the type in a C++17 fold function? Tim Rentsch <tr.17687@z991.linuxsc.com> - 2022-12-28 16:41 -0800
            Re: How can I get the type in a C++17 fold function? Bonita Montero <Bonita.Montero@gmail.com> - 2022-12-29 03:40 +0100
              Re: How can I get the type in a C++17 fold function? Tim Rentsch <tr.17687@z991.linuxsc.com> - 2022-12-28 22:27 -0800
            Re: How can I get the type in a C++17 fold function? Paavo Helde <eesnimi@osa.pri.ee> - 2022-12-29 09:36 +0200
              Re: How can I get the type in a C++17 fold function? Mason <mason.nobody@gmail.com> - 2022-12-29 17:15 +0000
                Re: How can I get the type in a C++17 fold function? "Alf P. Steinbach" <alf.p.steinbach@gmail.com> - 2022-12-29 19:11 +0100
              Re: How can I get the type in a C++17 fold function? Tim Rentsch <tr.17687@z991.linuxsc.com> - 2022-12-29 19:58 -0800
                Re: How can I get the type in a C++17 fold function? Bonita Montero <Bonita.Montero@gmail.com> - 2022-12-30 08:09 +0100
              Re: How can I get the type in a C++17 fold function? Michael S <already5chosen@yahoo.com> - 2022-12-30 03:27 -0800
                Re: How can I get the type in a C++17 fold function? "Alf P. Steinbach" <alf.p.steinbach@gmail.com> - 2022-12-30 14:01 +0100
                Re: How can I get the type in a C++17 fold function? Muttley@dastardlyhq.com - 2022-12-30 15:17 +0000
                Re: How can I get the type in a C++17 fold function? "Alf P. Steinbach" <alf.p.steinbach@gmail.com> - 2022-12-30 20:04 +0100
                Re: How can I get the type in a C++17 fold function? "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2022-12-30 13:54 -0800
                Re: How can I get the type in a C++17 fold function? Muttley@dastardlyhq.com - 2022-12-31 15:33 +0000
                Re: How can I get the type in a C++17 fold function? Jorgen Grahn <grahn+nntp@snipabacken.se> - 2022-12-30 17:31 +0000
                Re: How can I get the type in a C++17 fold function? Tim Rentsch <tr.17687@z991.linuxsc.com> - 2023-01-02 13:30 -0800
                Re: How can I get the type in a C++17 fold function? Bonita Montero <Bonita.Montero@gmail.com> - 2022-12-30 18:36 +0100

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