Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]

Groups > comp.lang.c > #99329

Re: Sum using variadic macros

Show all headers | View raw

Thiago Adams <thiago.adams@gmail.com> writes:

> Is it possible to do a sum with variadic macros?
>
> SUM('a', 'b', 'c') 
>
> I want to expand to 'a' + 'b' + 'c'

If you can accept a maximum number of arguments and the operation has an
identity element you can so this:

#define sum(...) (sum2(__VA_ARGS__, 0, 0, 0, 0, 0, 0, 0, 0))
#define sum2(a, b, c, d, e, f, g, h, ...) a + b + c + d + e + f + g + h

<snip>
> What I was planning to do is to generate a hash.
> HASH('t', 'h', 'i', 's');

Maybe.  That depends on the hash computation.

-- 
Ben.

Back to comp.lang.c | Previous | Next — Previous in thread | Next in thread | Find similar | Unroll thread

Thread

Sum using variadic macros Thiago Adams <thiago.adams@gmail.com> - 2016-12-14 02:54 -0800
  Re: Sum using variadic macros Ben Bacarisse <ben.usenet@bsb.me.uk> - 2016-12-14 11:51 +0000
    Re: Sum using variadic macros David Brown <david.brown@hesbynett.no> - 2016-12-14 13:58 +0100
      Re: Sum using variadic macros Richard Heathfield <rjh@cpax.org.uk> - 2016-12-14 14:01 +0000
      Re: Sum using variadic macros Thiago Adams <thiago.adams@gmail.com> - 2016-12-14 08:05 -0800
        Re: Sum using variadic macros BartC <bc@freeuk.com> - 2016-12-14 19:20 +0000
          Re: Sum using variadic macros Thiago Adams <thiago.adams@gmail.com> - 2016-12-14 11:26 -0800
            Re: Sum using variadic macros BartC <bc@freeuk.com> - 2016-12-14 20:06 +0000
    Re: Sum using variadic macros Thiago Adams <thiago.adams@gmail.com> - 2016-12-14 05:25 -0800
      Re: Sum using variadic macros mark.bluemel@gmail.com - 2016-12-14 08:10 -0800
        Re: Sum using variadic macros Thiago Adams <thiago.adams@gmail.com> - 2016-12-14 08:23 -0800
          Re: Sum using variadic macros Malcolm McLean <malcolm.mclean5@btinternet.com> - 2016-12-14 11:32 -0800
      Re: Sum using variadic macros Ben Bacarisse <ben.usenet@bsb.me.uk> - 2016-12-14 16:26 +0000
        Re: Sum using variadic macros David Brown <david.brown@hesbynett.no> - 2016-12-14 19:09 +0100
          Re: Sum using variadic macros supercat@casperkitty.com - 2016-12-14 11:33 -0800
          Re: Sum using variadic macros Ben Bacarisse <ben.usenet@bsb.me.uk> - 2016-12-14 19:40 +0000

csiph-web