Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]
| From | Keith Thompson <kst-u@mib.org> |
|---|---|
| Newsgroups | comp.lang.c |
| Subject | Re: Can "enum" be forced to a certain "bitness"? |
| Date | 2015-09-08 15:48 -0700 |
| Organization | None to speak of |
| Message-ID | <lnmvwwr0hq.fsf@kst-u.example.com> (permalink) |
| References | <msnbio$t7a$1@dont-email.me> <87lhcgoh4j.fsf@bsb.me.uk> <2c4d7c17-8b7d-4ea2-aa7d-73d8de39eb49@googlegroups.com> <msnma3$cig$1@dont-email.me> |
Bartc <bc@freeuk.com> writes:
> On 08/09/2015 22:57, Rick C. Hodgin wrote:
>> On Tuesday, September 8, 2015 at 3:17:41 PM UTC-4, Ben Bacarisse wrote:
>>> Ken Brody <kenbrody@spamcop.net> writes:
>>>> Can an enum be forced to a certain "bitness"?
>>>> For example, can I force an enum to be "int16_t"?
>>>
>>> No.
>>
>> This is a fundamental flaw in the language.
>
> I don't agree.
>
> Take:
>
> enum (red,green,blue,yellow);
>
> That's just a way of writing:
>
> #define red 0
> #define green 1
> etc
>
> What type is 0 or 1? Isn't it 'int' just like the enum?
Yes. To expand on that, the constants 0 and 1 are of type int because
the standard says so. Enumeration constants are of type int because the
standard says so in a different rule.
> So an enum is just a bunch of named values; it's not really a 'storage'
> type where you need to specify a narrow int or char type or even a 2-bit
> field. That can be specified separately if it's important.
But an enumeration *type* is a distinct type. For example, given:
enum color { red, green, blue, yellow };
enum color obj = blue;
the constants `red` et al are constant expressions of type int, but
`obj` is of type `enum color`. The type `enum color` is compatible with
some implementation-defined integer type (gcc happens to use unsigned
int); that type must be able to hold the values of all the constants.
Which means, for example, that the initialization of `obj` may involve
an implicit conversion.
[...]
--
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
Can "enum" be forced to a certain "bitness"? Ken Brody <kenbrody@spamcop.net> - 2015-09-08 15:07 -0400
Re: Can "enum" be forced to a certain "bitness"? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2015-09-08 20:17 +0100
Re: Can "enum" be forced to a certain "bitness"? Keith Thompson <kst-u@mib.org> - 2015-09-08 12:36 -0700
Re: Can "enum" be forced to a certain "bitness"? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2015-09-08 22:52 +0100
Re: Can "enum" be forced to a certain "bitness"? Ken Brody <kenbrody@spamcop.net> - 2015-09-09 11:40 -0400
Re: Can "enum" be forced to a certain "bitness"? "Rick C. Hodgin" <rick.c.hodgin@gmail.com> - 2015-09-08 14:57 -0700
Re: Can "enum" be forced to a certain "bitness"? Bartc <bc@freeuk.com> - 2015-09-08 23:10 +0100
Re: Can "enum" be forced to a certain "bitness"? "Rick C. Hodgin" <rick.c.hodgin@gmail.com> - 2015-09-08 15:15 -0700
Re: Can "enum" be forced to a certain "bitness"? Ian Collins <ian-news@hotmail.com> - 2015-09-09 10:35 +1200
Re: Can "enum" be forced to a certain "bitness"? David Brown <david.brown@hesbynett.no> - 2015-09-09 11:07 +0200
Re: Can "enum" be forced to a certain "bitness"? Bartc <bc@freeuk.com> - 2015-09-09 12:36 +0100
Re: Can "enum" be forced to a certain "bitness"? David Brown <david.brown@hesbynett.no> - 2015-09-09 13:46 +0200
Re: Can "enum" be forced to a certain "bitness"? Ian Collins <ian-news@hotmail.com> - 2015-09-11 11:32 +1200
Re: Can "enum" be forced to a certain "bitness"? Keith Thompson <kst-u@mib.org> - 2015-09-10 17:39 -0700
Re: Can "enum" be forced to a certain "bitness"? David Brown <david.brown@hesbynett.no> - 2015-09-11 09:03 +0200
Re: Can "enum" be forced to a certain "bitness"? Keith Thompson <kst-u@mib.org> - 2015-09-11 11:33 -0700
Re: Can "enum" be forced to a certain "bitness"? Ian Collins <ian-news@hotmail.com> - 2015-09-11 21:24 +1200
Re: Can "enum" be forced to a certain "bitness"? David Brown <david.brown@hesbynett.no> - 2015-09-11 11:38 +0200
Re: Can "enum" be forced to a certain "bitness"? Richard Heathfield <rjh@cpax.org.uk> - 2015-09-11 10:40 +0100
Re: Can "enum" be forced to a certain "bitness"? David Brown <david.brown@hesbynett.no> - 2015-09-11 12:51 +0200
Re: Can "enum" be forced to a certain "bitness"? Les Cargill <lcargill99@comcast.com> - 2015-09-11 12:21 -0500
Re: Can "enum" be forced to a certain "bitness"? supercat@casperkitty.com - 2015-09-11 15:03 -0700
Re: Can "enum" be forced to a certain "bitness"? David Brown <david.brown@hesbynett.no> - 2015-09-12 15:01 +0200
Re: Can "enum" be forced to a certain "bitness"? David Brown <david.brown@hesbynett.no> - 2015-09-11 09:23 +0200
Re: Can "enum" be forced to a certain "bitness"? David Brown <david.brown@hesbynett.no> - 2015-09-10 10:06 +0200
Re: Can "enum" be forced to a certain "bitness"? David Kleinecke <dkleinecke@gmail.com> - 2015-09-15 17:55 -0700
Re: Can "enum" be forced to a certain "bitness"? Lew Pitcher <lew.pitcher@digitalfreehold.ca> - 2015-09-08 18:36 -0400
Re: Can "enum" be forced to a certain "bitness"? Keith Thompson <kst-u@mib.org> - 2015-09-08 16:14 -0700
Re: Can "enum" be forced to a certain "bitness"? Lew Pitcher <lew.pitcher@digitalfreehold.ca> - 2015-09-08 19:49 -0400
Re: Can "enum" be forced to a certain "bitness"? Keith Thompson <kst-u@mib.org> - 2015-09-08 17:20 -0700
Re: Can "enum" be forced to a certain "bitness"? Keith Thompson <kst-u@mib.org> - 2015-09-08 15:48 -0700
Re: Can "enum" be forced to a certain "bitness"? "Rick C. Hodgin" <rick.c.hodgin@gmail.com> - 2015-09-08 16:03 -0700
Re: Can "enum" be forced to a certain "bitness"? Ian Collins <ian-news@hotmail.com> - 2015-09-09 11:16 +1200
Re: Can "enum" be forced to a certain "bitness"? "Rick C. Hodgin" <rick.c.hodgin@gmail.com> - 2015-09-08 16:18 -0700
Re: Can "enum" be forced to a certain "bitness"? "Rick C. Hodgin" <rick.c.hodgin@gmail.com> - 2015-09-08 16:19 -0700
Re: Can "enum" be forced to a certain "bitness"? Ian Collins <ian-news@hotmail.com> - 2015-09-09 11:42 +1200
Re: Can "enum" be forced to a certain "bitness"? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2015-09-09 00:52 +0100
Re: Can "enum" be forced to a certain "bitness"? David Brown <david.brown@hesbynett.no> - 2015-09-09 13:28 +0200
Re: Can "enum" be forced to a certain "bitness"? Keith Thompson <kst-u@mib.org> - 2015-09-09 10:56 -0700
Re: Can "enum" be forced to a certain "bitness"? David Brown <david.brown@hesbynett.no> - 2015-09-09 22:17 +0200
Re: Can "enum" be forced to a certain "bitness"? Philip Lantz <prl@canterey.us> - 2015-09-08 22:06 -0700
Re: Can "enum" be forced to a certain "bitness"? Keith Thompson <kst-u@mib.org> - 2015-09-08 23:14 -0700
Re: Can "enum" be forced to a certain "bitness"? supercat@casperkitty.com - 2015-09-09 16:10 -0700
Re: Can "enum" be forced to a certain "bitness"? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2015-09-09 00:42 +0100
Re: Can "enum" be forced to a certain "bitness"? "Rick C. Hodgin" <rick.c.hodgin@gmail.com> - 2015-09-08 16:55 -0700
Re: Can "enum" be forced to a certain "bitness"? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2015-09-09 01:31 +0100
Re: Can "enum" be forced to a certain "bitness"? "Rick C. Hodgin" <rick.c.hodgin@gmail.com> - 2015-09-08 17:51 -0700
Re: Can "enum" be forced to a certain "bitness"? Les Cargill <lcargill99@comcast.com> - 2015-09-08 22:53 -0500
Re: Can "enum" be forced to a certain "bitness"? Bartc <bc@freeuk.com> - 2015-09-09 10:00 +0100
Re: Can "enum" be forced to a certain "bitness"? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2015-09-09 11:27 +0100
Re: Can "enum" be forced to a certain "bitness"? David Brown <david.brown@hesbynett.no> - 2015-09-09 13:31 +0200
Re: Can "enum" be forced to a certain "bitness"? Les Cargill <lcargill99@comcast.com> - 2015-09-09 18:32 -0500
Re: Can "enum" be forced to a certain "bitness"? Keith Thompson <kst-u@mib.org> - 2015-09-09 17:15 -0700
Re: Can "enum" be forced to a certain "bitness"? Les Cargill <lcargill99@comcast.com> - 2015-09-09 18:29 -0500
Re: Can "enum" be forced to a certain "bitness"? Keith Thompson <kst-u@mib.org> - 2015-09-09 17:10 -0700
Re: Can "enum" be forced to a certain "bitness"? Les Cargill <lcargill99@comcast.com> - 2015-09-09 22:27 -0500
Re: Can "enum" be forced to a certain "bitness"? Keith Thompson <kst-u@mib.org> - 2015-09-09 21:09 -0700
Re: Can "enum" be forced to a certain "bitness"? Les Cargill <lcargill99@comcast.com> - 2015-09-10 01:54 -0500
Re: Can "enum" be forced to a certain "bitness"? Keith Thompson <kst-u@mib.org> - 2015-09-10 10:57 -0700
Re: Can "enum" be forced to a certain "bitness"? James Kuyper <jameskuyper@verizon.net> - 2015-09-10 00:21 -0400
Re: Can "enum" be forced to a certain "bitness"? Les Cargill <lcargill99@comcast.com> - 2015-09-10 02:00 -0500
Re: Can "enum" be forced to a certain "bitness"? James Kuyper <jameskuyper@verizon.net> - 2015-09-10 09:32 -0400
Re: Can "enum" be forced to a certain "bitness"? fir <profesor.fir@gmail.com> - 2015-09-09 08:19 -0700
Re: Can "enum" be forced to a certain "bitness"? fir <profesor.fir@gmail.com> - 2015-09-09 08:43 -0700
Re: Can "enum" be forced to a certain "bitness"? "Rick C. Hodgin" <rick.c.hodgin@gmail.com> - 2015-09-09 13:05 -0700
Re: Can "enum" be forced to a certain "bitness"? "Rick C. Hodgin" <rick.c.hodgin@gmail.com> - 2015-09-09 13:10 -0700
Re: Can "enum" be forced to a certain "bitness"? fir <profesor.fir@gmail.com> - 2015-09-10 00:47 -0700
Re: Can "enum" be forced to a certain "bitness"? fir <profesor.fir@gmail.com> - 2015-09-10 01:05 -0700
Re: Can "enum" be forced to a certain "bitness"? fir <profesor.fir@gmail.com> - 2015-09-10 02:04 -0700
Re: Can "enum" be forced to a certain "bitness"? Bartc <bc@freeuk.com> - 2015-09-10 10:30 +0100
Re: Can "enum" be forced to a certain "bitness"? fir <profesor.fir@gmail.com> - 2015-09-10 06:33 -0700
Re: Can "enum" be forced to a certain "bitness"? fir <profesor.fir@gmail.com> - 2015-09-10 06:43 -0700
Re: Can "enum" be forced to a certain "bitness"? fir <profesor.fir@gmail.com> - 2015-09-15 15:22 -0700
Re: Can "enum" be forced to a certain "bitness"? fir <profesor.fir@gmail.com> - 2015-09-10 01:35 -0700
Re: Can "enum" be forced to a certain "bitness"? Eric Sosman <esosman@comcast-dot-net.invalid> - 2015-09-08 15:38 -0400
Re: Can "enum" be forced to a certain "bitness"? Tim Rentsch <txr@alumni.caltech.edu> - 2015-09-09 10:52 -0700
Re: Can "enum" be forced to a certain "bitness"? David Thompson <dave.thompson2@verizon.net> - 2015-09-20 18:35 -0400
Re: Can "enum" be forced to a certain "bitness"? Tim Rentsch <txr@alumni.caltech.edu> - 2015-09-26 16:30 -0700
Re: Can "enum" be forced to a certain "bitness"? Tim Rentsch <txr@alumni.caltech.edu> - 2015-09-26 16:51 -0700
Re: Can "enum" be forced to a certain "bitness"? James Kuyper <jameskuyper@verizon.net> - 2015-09-08 15:50 -0400
Re: Can "enum" be forced to a certain "bitness"? Jorgen Grahn <grahn+nntp@snipabacken.se> - 2015-09-08 20:25 +0000
Re: Can "enum" be forced to a certain "bitness"? David Brown <david.brown@hesbynett.no> - 2015-09-08 23:09 +0200
csiph-web