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Groups > comp.lang.c++ > #84225
| From | Paavo Helde <eesnimi@osa.pri.ee> |
|---|---|
| Newsgroups | comp.lang.c++ |
| Subject | Re: Constexpr evaluation of heavy stuff |
| Date | 2022-05-20 22:31 +0300 |
| Organization | A noiseless patient Spider |
| Message-ID | <t68qa0$8b9$1@dont-email.me> (permalink) |
| References | (11 earlier) <t67rjj$kk3$1@dont-email.me> <87czg85udt.fsf@bsb.me.uk> <8dc30c48-e2ee-43e8-93fb-79f54704b879n@googlegroups.com> <t687pk$ilc$1@dont-email.me> <t68hah$uuh$1@dont-email.me> |
20.05.2022 19:57 Christian Gollwitzer kirjutas:
> Am 20.05.22 um 16:15 schrieb Paavo Helde:
>> 20.05.2022 16:33 Öö Tiib kirjutas:
>>
>>> Modular arithmetic around likes of 42949672956 however is typically
>>> utterly useless.
>> I agree in general, but I have found one use case. Suppose we have a
>> string s which might or might not contain a separator like ':' and we
>> want to either return the part after separator, or the whole string if
>> there is no separator. This is the code:
>>
>> return s.substr(s.find(':')+1);
>>
> And where exactly do you need mod "ridiculous number" here? WHy is that
> better than having a signed index variable, where negative values
> indicate invalid indices?
You are right, if std::string::find() returned a signed integer -1 for
no-find, this code would work just as fine. The only thing is that it
doesn't work that way, it returns size_t(-1) which is typically
18446744073709551615ULL nowadays.
Coming to think of that, the only usage of unsigned types in my code
happens because the C++ standard library uses them for size_t and
related types.
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Constexpr evaluation of heavy stuff Andrey Tarasevich <andreytarasevich@hotmail.com> - 2022-05-18 16:17 -0700
Re: Constexpr evaluation of heavy stuff "Alf P. Steinbach" <alf.p.steinbach@gmail.com> - 2022-05-19 09:19 +0200
Re: Constexpr evaluation of heavy stuff David Brown <david.brown@hesbynett.no> - 2022-05-19 11:59 +0200
Re: Constexpr evaluation of heavy stuff "Alf P. Steinbach" <alf.p.steinbach@gmail.com> - 2022-05-19 12:37 +0200
Re: Constexpr evaluation of heavy stuff David Brown <david.brown@hesbynett.no> - 2022-05-19 14:49 +0200
Re: Constexpr evaluation of heavy stuff Malcolm McLean <malcolm.arthur.mclean@gmail.com> - 2022-05-19 06:19 -0700
Re: Constexpr evaluation of heavy stuff Paavo Helde <eesnimi@osa.pri.ee> - 2022-05-19 20:32 +0300
Re: Constexpr evaluation of heavy stuff Malcolm McLean <malcolm.arthur.mclean@gmail.com> - 2022-05-20 01:12 -0700
Re: Constexpr evaluation of heavy stuff Juha Nieminen <nospam@thanks.invalid> - 2022-05-20 08:37 +0000
Re: Constexpr evaluation of heavy stuff Malcolm McLean <malcolm.arthur.mclean@gmail.com> - 2022-05-20 02:21 -0700
Re: Constexpr evaluation of heavy stuff Ben <ben.usenet@bsb.me.uk> - 2022-05-20 11:25 +0100
Re: Constexpr evaluation of heavy stuff David Brown <david.brown@hesbynett.no> - 2022-05-20 12:47 +0200
Re: Constexpr evaluation of heavy stuff Ben <ben.usenet@bsb.me.uk> - 2022-05-20 12:13 +0100
Re: Constexpr evaluation of heavy stuff David Brown <david.brown@hesbynett.no> - 2022-05-20 14:27 +0200
Re: Constexpr evaluation of heavy stuff Öö Tiib <ootiib@hot.ee> - 2022-05-20 06:33 -0700
Re: Constexpr evaluation of heavy stuff Paavo Helde <eesnimi@osa.pri.ee> - 2022-05-20 17:15 +0300
Re: Constexpr evaluation of heavy stuff Christian Gollwitzer <auriocus@gmx.de> - 2022-05-20 18:57 +0200
Re: Constexpr evaluation of heavy stuff Paavo Helde <eesnimi@osa.pri.ee> - 2022-05-20 22:31 +0300
Re: Constexpr evaluation of heavy stuff Manfred <noname@add.invalid> - 2022-05-21 21:56 +0200
Re: Constexpr evaluation of heavy stuff Öö Tiib <ootiib@hot.ee> - 2022-05-21 23:24 -0700
Re: Constexpr evaluation of heavy stuff Malcolm McLean <malcolm.arthur.mclean@gmail.com> - 2022-05-22 04:56 -0700
Re: Constexpr evaluation of heavy stuff Öö Tiib <ootiib@hot.ee> - 2022-05-22 06:15 -0700
Re: Constexpr evaluation of heavy stuff Manfred <noname@add.invalid> - 2022-05-22 21:46 +0200
Re: Constexpr evaluation of heavy stuff "Alf P. Steinbach" <alf.p.steinbach@gmail.com> - 2022-05-22 23:23 +0200
Re: Constexpr evaluation of heavy stuff Malcolm McLean <malcolm.arthur.mclean@gmail.com> - 2022-05-22 16:26 -0700
Re: Constexpr evaluation of heavy stuff Manfred <noname@add.invalid> - 2022-05-23 17:24 +0200
Re: Constexpr evaluation of heavy stuff Richard Damon <Richard@Damon-Family.org> - 2022-05-23 19:41 -0400
Re: Constexpr evaluation of heavy stuff scott@slp53.sl.home (Scott Lurndal) - 2022-05-24 16:15 +0000
Re: Constexpr evaluation of heavy stuff Tim Rentsch <tr.17687@z991.linuxsc.com> - 2022-05-24 05:37 -0700
Re: Constexpr evaluation of heavy stuff Malcolm McLean <malcolm.arthur.mclean@gmail.com> - 2022-05-20 04:19 -0700
Re: Constexpr evaluation of heavy stuff Ben <ben.usenet@bsb.me.uk> - 2022-05-20 12:32 +0100
Re: Constexpr evaluation of heavy stuff Juha Nieminen <nospam@thanks.invalid> - 2022-05-20 10:40 +0000
Re: Constexpr evaluation of heavy stuff David Brown <david.brown@hesbynett.no> - 2022-05-20 12:31 +0200
Re: Constexpr evaluation of heavy stuff Juha Nieminen <nospam@thanks.invalid> - 2022-05-20 10:43 +0000
Re: Constexpr evaluation of heavy stuff David Brown <david.brown@hesbynett.no> - 2022-05-20 14:52 +0200
Re: Constexpr evaluation of heavy stuff "Alf P. Steinbach" <alf.p.steinbach@gmail.com> - 2022-05-19 15:34 +0200
Re: Constexpr evaluation of heavy stuff "Alf P. Steinbach" <alf.p.steinbach@gmail.com> - 2022-05-19 17:03 +0200
Re: Constexpr evaluation of heavy stuff Tim Rentsch <tr.17687@z991.linuxsc.com> - 2022-05-19 08:53 -0700
Re: Constexpr evaluation of heavy stuff Marcel Mueller <news.5.maazl@spamgourmet.org> - 2022-05-19 18:33 +0200
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