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| From | Keith Thompson <kst-u@mib.org> |
|---|---|
| Newsgroups | comp.lang.c |
| Subject | Re: Why _Bool was not defined as enum in C99? |
| Date | 2016-09-14 16:26 -0700 |
| Organization | None to speak of |
| Message-ID | <lnr38m3vwh.fsf@kst-u.example.com> (permalink) |
| References | <6b5aa241-0498-4e41-993b-a1ed445effb0@googlegroups.com> <871t0osuq6.fsf@bsb.me.uk> <kfn8tuvjt8u.fsf@x-alumni2.alumni.caltech.edu> <lnpoo75lfc.fsf@kst-u.example.com> <15road-l18.ln1@wilbur.25thandClement.com> |
<william@wilbur.25thandClement.com> writes:
> Keith Thompson <kst-u@mib.org> wrote:
>> Tim Rentsch <txr@alumni.caltech.edu> writes:
>>> Ben Bacarisse <ben.usenet@bsb.me.uk> writes:
>>>
>>>> thiago.adams@gmail.com writes:
>>>>
>>>>> Does anyone knows if an enumeration was considered to implement _Bool?
>>>>
>>>> I image a strong reason it would not have got through is the desire to
>>>> be compatible with the semantics of C++'s bool which does not behave
>>>> like an enumerated type. [...]
>>>
>>> I believe bool in C++ and _Bool in C were developed more or less
>>> contemporaneously. (C++ added 'bool' in C++98.) That doesn't
>>> contradict your statement, but it suggests the relationship
>>> may have been one more of synergy than causality. (Let me
>>> emphasize that I have no facts beyond when 'bool' was added
>>> to C++. I don't know anything, I'm just speculating.)
>>
>> Hmm. C++98 was the first C++ standard. Did pre-standard C++
>> not have bool before that? (I have books that would answer that,
>> but they're not handy.)
>>
>> (The C99 Rationale doesn't provide any useful information on the
>> history of _Bool.)
>
> I don't know if this was the proposal actually adopted, but there's a
> rationale included in N815 which explains, in part,
>
> "The solution is to standardize a Boolean type. This could have been
> implemented in any one of the ways that C developers have used in the
> past, or as a type built into the language. The committee chose the latter
> because it is linguistically cleaner. It gives the translator direct
> knowledge of the type, which allows consistent promotion rules to be
> defined and which may expose new opportunities for optimization as well."
>
> -- http://www.open-std.org/jtc1/sc22/wg14/www/docs/n815.htm
>
> N815 is one of the first hits when using the Google search
>
> site:http://www.open-std.org/jtc1/sc22/wg14/www/docs _Bool
Interesting, thanks.
The changes described in N815 are very close to what's in C99. (There
may be a few minor wording changes; I haven't checked.)
Note that there's no mention of C++ -- which neither confirms nor denies
that C's _Bool was inspired by C++'s bool.
In the Conclusion section, it says:
The above changes will bring C9X into alignment with the committee's
decision by adding a first class Boolean type.
Which implies that there was a decision, perhaps documented in some
minutes somewhere, that preceded the writing of N815.
--
Keith Thompson (The_Other_Keith) kst-u@mib.org <http://www.ghoti.net/~kst>
Working, but not speaking, for JetHead Development, Inc.
"We must do something. This is something. Therefore, we must do this."
-- Antony Jay and Jonathan Lynn, "Yes Minister"
Back to comp.lang.c | Previous | Next — Previous in thread | Next in thread | Find similar | Unroll thread
Why _Bool was not defined as enum in C99? thiago.adams@gmail.com - 2016-09-12 13:24 -0700
Re: Why _Bool was not defined as enum in C99? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2016-09-12 21:56 +0100
Re: Why _Bool was not defined as enum in C99? Keith Thompson <kst-u@mib.org> - 2016-09-12 15:59 -0700
Re: Why _Bool was not defined as enum in C99? Tim Rentsch <txr@alumni.caltech.edu> - 2016-09-13 16:05 -0700
Re: Why _Bool was not defined as enum in C99? Keith Thompson <kst-u@mib.org> - 2016-09-13 18:17 -0700
Re: Why _Bool was not defined as enum in C99? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2016-09-14 01:20 +0100
Re: Why _Bool was not defined as enum in C99? Tim Rentsch <txr@alumni.caltech.edu> - 2016-09-14 03:59 -0700
Re: Why _Bool was not defined as enum in C99? Nobody <nobody@nowhere.invalid> - 2016-09-14 17:31 +0100
Re: Why _Bool was not defined as enum in C99? Thiago Adams <thiago.adams@gmail.com> - 2016-09-14 09:49 -0700
Re: Why _Bool was not defined as enum in C99? Keith Thompson <kst-u@mib.org> - 2016-09-14 11:45 -0700
Re: Why _Bool was not defined as enum in C99? <william@wilbur.25thandClement.com> - 2016-09-14 14:13 -0700
Re: Why _Bool was not defined as enum in C99? Keith Thompson <kst-u@mib.org> - 2016-09-14 16:26 -0700
Re: Why _Bool was not defined as enum in C99? "James R. Kuyper" <jameskuyper@verizon.net> - 2016-09-12 17:11 -0400
Re: Why _Bool was not defined as enum in C99? Tim Rentsch <txr@alumni.caltech.edu> - 2016-09-13 15:55 -0700
Re: Why _Bool was not defined as enum in C99? Keith Thompson <kst-u@mib.org> - 2016-09-13 18:08 -0700
Re: Why _Bool was not defined as enum in C99? Tim Rentsch <txr@alumni.caltech.edu> - 2016-09-14 03:56 -0700
Re: Why _Bool was not defined as enum in C99? supercat@casperkitty.com - 2016-09-14 07:58 -0700
Re: Why _Bool was not defined as enum in C99? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2016-09-14 19:39 +0100
Re: Why _Bool was not defined as enum in C99? Keith Thompson <kst-u@mib.org> - 2016-09-14 13:52 -0700
Re: Why _Bool was not defined as enum in C99? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2016-09-15 00:53 +0100
Re: Why _Bool was not defined as enum in C99? supercat@casperkitty.com - 2016-09-14 17:04 -0700
Re: Why _Bool was not defined as enum in C99? Keith Thompson <kst-u@mib.org> - 2016-09-14 20:52 -0700
Re: Why _Bool was not defined as enum in C99? supercat@casperkitty.com - 2016-09-14 19:26 -0700
Re: Why _Bool was not defined as enum in C99? Keith Thompson <kst-u@mib.org> - 2016-09-14 19:04 -0700
Re: Why _Bool was not defined as enum in C99? supercat@casperkitty.com - 2016-09-14 14:21 -0700
Re: Why _Bool was not defined as enum in C99? Keith Thompson <kst-u@mib.org> - 2016-09-14 16:23 -0700
Re: Why _Bool was not defined as enum in C99? supercat@casperkitty.com - 2016-09-14 17:06 -0700
Re: Why _Bool was not defined as enum in C99? Keith Thompson <kst-u@mib.org> - 2016-09-14 20:45 -0700
Re: Why _Bool was not defined as enum in C99? Jerry Stuckle <jstucklex@attglobal.net> - 2016-09-14 22:12 -0400
Re: Why _Bool was not defined as enum in C99? David Brown <david.brown@hesbynett.no> - 2016-09-15 12:37 +0200
Re: Why _Bool was not defined as enum in C99? supercat@casperkitty.com - 2016-09-15 09:35 -0700
Re: Why _Bool was not defined as enum in C99? David Brown <david.brown@hesbynett.no> - 2016-09-16 00:47 +0200
Re: Why _Bool was not defined as enum in C99? supercat@casperkitty.com - 2016-09-15 22:02 -0700
Re: Why _Bool was not defined as enum in C99? David Brown <david.brown@hesbynett.no> - 2016-09-16 09:56 +0200
Re: Why _Bool was not defined as enum in C99? supercat@casperkitty.com - 2016-09-16 07:34 -0700
Re: Why _Bool was not defined as enum in C99? David Brown <david.brown@hesbynett.no> - 2016-09-16 20:31 +0200
Re: Why _Bool was not defined as enum in C99? supercat@casperkitty.com - 2016-09-16 12:32 -0700
Re: Why _Bool was not defined as enum in C99? David Brown <david.brown@hesbynett.no> - 2016-09-17 23:30 +0200
Re: Why _Bool was not defined as enum in C99? BartC <bc@freeuk.com> - 2016-09-15 18:25 +0100
Re: Why _Bool was not defined as enum in C99? luser droog <luser.droog@gmail.com> - 2016-09-15 12:35 -0700
Re: Why _Bool was not defined as enum in C99? David Brown <david.brown@hesbynett.no> - 2016-09-16 00:51 +0200
Re: Why _Bool was not defined as enum in C99? luser droog <luser.droog@gmail.com> - 2016-09-16 17:02 -0700
Re: Why _Bool was not defined as enum in C99? Keith Thompson <kst-u@mib.org> - 2016-09-16 19:23 -0700
Re: Why _Bool was not defined as enum in C99? David Brown <david.brown@hesbynett.no> - 2016-09-17 23:35 +0200
Re: Why _Bool was not defined as enum in C99? Keith Thompson <kst-u@mib.org> - 2016-09-14 10:40 -0700
Re: Why _Bool was not defined as enum in C99? Thiago Adams <thiago.adams@gmail.com> - 2016-09-14 10:01 -0700
Re: Why _Bool was not defined as enum in C99? supercat@casperkitty.com - 2016-09-14 11:35 -0700
Re: Why _Bool was not defined as enum in C99? Jerry Stuckle <jstucklex@attglobal.net> - 2016-09-14 22:15 -0400
Re: Why _Bool was not defined as enum in C99? supercat@casperkitty.com - 2016-09-14 23:51 -0700
Re: Why _Bool was not defined as enum in C99? Jerry Stuckle <jstucklex@attglobal.net> - 2016-09-15 15:14 -0400
Re: Why _Bool was not defined as enum in C99? Ian Collins <ian-news@hotmail.com> - 2016-09-15 16:08 +1200
Re: Why _Bool was not defined as enum in C99? David Brown <david.brown@hesbynett.no> - 2016-09-15 12:46 +0200
Re: Why _Bool was not defined as enum in C99? supercat@casperkitty.com - 2016-09-15 09:37 -0700
Re: Why _Bool was not defined as enum in C99? David Brown <david.brown@hesbynett.no> - 2016-09-16 00:53 +0200
Re: Why _Bool was not defined as enum in C99? supercat@casperkitty.com - 2016-09-15 21:45 -0700
Re: Why _Bool was not defined as enum in C99? Richard Heathfield <rjh@cpax.org.uk> - 2016-09-16 06:32 +0100
Re: Why _Bool was not defined as enum in C99? David Brown <david.brown@hesbynett.no> - 2016-09-16 09:59 +0200
Re: Why _Bool was not defined as enum in C99? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2016-09-16 11:00 +0100
Re: Why _Bool was not defined as enum in C99? Thiago Adams <thiago.adams@gmail.com> - 2016-09-16 04:46 -0700
Re: Why _Bool was not defined as enum in C99? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2016-09-16 12:58 +0100
Re: Why _Bool was not defined as enum in C99? Melzzzzz <Melzzzzz@zzzzz.com> - 2016-09-16 12:06 +0000
Re: Why _Bool was not defined as enum in C99? Thiago Adams <thiago.adams@gmail.com> - 2016-09-16 05:13 -0700
Re: Why _Bool was not defined as enum in C99? Keith Thompson <kst-u@mib.org> - 2016-09-16 10:47 -0700
Re: Why _Bool was not defined as enum in C99? Keith Thompson <kst-u@mib.org> - 2016-09-16 10:46 -0700
Re: Why _Bool was not defined as enum in C99? David Brown <david.brown@hesbynett.no> - 2016-09-16 10:02 +0200
Re: Why _Bool was not defined as enum in C99? Tim Rentsch <txr@alumni.caltech.edu> - 2016-09-15 11:42 -0700
Re: Why _Bool was not defined as enum in C99? David Brown <david.brown@hesbynett.no> - 2016-09-16 10:19 +0200
Re: Why _Bool was not defined as enum in C99? Tim Rentsch <txr@alumni.caltech.edu> - 2016-09-16 08:06 -0700
Re: Why _Bool was not defined as enum in C99? David Brown <david.brown@hesbynett.no> - 2016-09-16 20:51 +0200
Re: Why _Bool was not defined as enum in C99? Thiago Adams <thiago.adams@gmail.com> - 2016-09-16 11:56 -0700
Re: Why _Bool was not defined as enum in C99? Tim Rentsch <txr@alumni.caltech.edu> - 2016-09-22 22:38 -0700
Re: Why _Bool was not defined as enum in C99? Tim Rentsch <txr@alumni.caltech.edu> - 2016-09-14 11:42 -0700
Re: Why _Bool was not defined as enum in C99? Keith Thompson <kst-u@mib.org> - 2016-09-14 14:02 -0700
Re: Why _Bool was not defined as enum in C99? Tim Rentsch <txr@alumni.caltech.edu> - 2016-09-15 10:51 -0700
Re: Why _Bool was not defined as enum in C99? supercat@casperkitty.com - 2016-09-15 11:18 -0700
Re: Why _Bool was not defined as enum in C99? Keith Thompson <kst-u@mib.org> - 2016-09-15 13:46 -0700
Re: Why _Bool was not defined as enum in C99? supercat@casperkitty.com - 2016-09-15 13:10 -0700
Re: Why _Bool was not defined as enum in C99? Keith Thompson <kst-u@mib.org> - 2016-09-15 16:01 -0700
Re: Why _Bool was not defined as enum in C99? Keith Thompson <kst-u@mib.org> - 2016-09-15 13:40 -0700
Re: Why _Bool was not defined as enum in C99? Tim Rentsch <txr@alumni.caltech.edu> - 2016-09-16 07:21 -0700
Re: Why _Bool was not defined as enum in C99? Thiago Adams <thiago.adams@gmail.com> - 2016-09-16 07:37 -0700
Re: Why _Bool was not defined as enum in C99? David Brown <david.brown@hesbynett.no> - 2016-09-16 20:55 +0200
Re: Why _Bool was not defined as enum in C99? Keith Thompson <kst-u@mib.org> - 2016-09-16 14:43 -0700
Re: Why _Bool was not defined as enum in C99? supercat@casperkitty.com - 2016-09-16 15:36 -0700
Re: Why _Bool was not defined as enum in C99? David Brown <david.brown@hesbynett.no> - 2016-09-17 23:45 +0200
Re: Why _Bool was not defined as enum in C99? Keith Thompson <kst-u@mib.org> - 2016-09-17 17:14 -0700
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