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Groups > comp.lang.c > #156800
| From | Tim Rentsch <tr.17687@z991.linuxsc.com> |
|---|---|
| Newsgroups | comp.lang.c |
| Subject | Re: Is bool no longer a primitive data type of C/C++ ? |
| Date | 2020-11-29 00:14 -0800 |
| Organization | A noiseless patient Spider |
| Message-ID | <868sakr34t.fsf@linuxsc.com> (permalink) |
| References | (3 earlier) <875z6nu10d.fsf@bsb.me.uk> <w72dncKV3eO52T3CnZ2dnUU7-YfNnZ2d@giganews.com> <83458da8-c4fa-4a7f-acea-bb04b9d8ee3en@googlegroups.com> <-oidnSk6-K2g_D3CnZ2dnUU7-e3NnZ2d@giganews.com> <21562d54-68c2-4a39-99ad-ada14cce43f8n@googlegroups.com> |
"james...@alumni.caltech.edu" <jameskuyper@alumni.caltech.edu> writes:
> On Monday, November 2, 2020 at 2:43:14 PM UTC-5, olcott wrote:
>
>> On 11/2/2020 1:18 PM, james...@alumni.caltech.edu wrote:
>>
>>> On Monday, November 2, 2020 at 12:39:06 PM UTC-5, olcott wrote:
>>>
>>>> On 11/2/2020 11:22 AM, Ben Bacarisse wrote:
>>>
>>> ...
>>>
>>>>> K&R C never had bool. The second edition of K&R is essentially the same
>>>>> as the first ANSI and ISO standard, often called C90.
>>>>>
>>>>> _Bool (and stdbool.h) were introduced in C99.
>>>>
>>>> Apparently this works on older compilers:
>>>> enum Boolean{true, false};
>>>> typedef enum Boolean bool;
>>>
>>> In addition to the problem with true and false being reversed, there's
>>> an additional problem. _Bool in C (and bool in C++) has a special
>>> properties that cannot be reproduced by simply making bool a typedef
>>> for an ordinary integer type: conversion of a value 'x' of any real or
>>> pointer type to bool type produces the same result as x!=0.
>>
>> enum Boolean{false, true};
>> typedef enum Boolean bool;
>>
>>
>> int main()
>> {
>> bool X = 5 > 7;
>> bool Y = 7 > 5;
>>
>> if (X)
>> printf("X is true\n");
>> if (!X)
>> printf("X is false\n");
>> if (Y)
>> printf("Y is true\n");
>> if (!Y)
>> printf("Y is false\n");
>> }
>>
>> Output:
>> X is false
>> Y is true
>
> Try this: printf("(bool)5 is %d\n", (bool)5);
>
> In C99 or greater, with 'bool' defined by <stdbool.h>, the output is
> required to be "(boo)5 is 1". As a result, if X has the type bool,
> if(X) and if(X==true) have the same meaning.
>
> No typedef for bool as an ordinary integer type can duplicate that
> behavior.
Is there anything in the C standard that would preclude the
type 'enum Boolean{false, true}' from having a compatible
type of _Bool? I looked but didn't see anything.
Back to comp.lang.c | Previous | Next — Previous in thread | Next in thread | Find similar | Unroll thread
Is bool no longer a primitive data type of C/C++ ? olcott <NoOne@NoWhere.com> - 2020-11-02 10:31 -0600
Re: Is bool no longer a primitive data type of C/C++ ? Bonita Montero <Bonita.Montero@gmail.com> - 2020-11-02 17:35 +0100
Re: Is bool no longer a primitive data type of C/C++ ? olcott <NoOne@NoWhere.com> - 2020-11-02 10:39 -0600
Re: Is bool no longer a primitive data type of C/C++ ? Bonita Montero <Bonita.Montero@gmail.com> - 2020-11-02 17:55 +0100
Re: Is bool no longer a primitive data type of C/C++ ? guinness.tony@gmail.com - 2020-11-02 09:00 -0800
Re: Is bool no longer a primitive data type of C/C++ ? Leo <usenet@gkbrk.com> - 2020-11-03 19:50 +0300
Re: Is bool no longer a primitive data type of C/C++ ? James Kuyper <jameskuyper@alumni.caltech.edu> - 2020-11-03 12:43 -0500
Re: Is bool no longer a primitive data type of C/C++ ? "Alf P. Steinbach" <alf.p.steinbach+usenet@gmail.com> - 2020-11-02 17:48 +0100
Re: Is bool no longer a primitive data type of C/C++ ? olcott <NoOne@NoWhere.com> - 2020-11-02 10:50 -0600
Re: Is bool no longer a primitive data type of C/C++ ? Joe Pfeiffer <pfeiffer@cs.nmsu.edu> - 2020-11-02 10:35 -0700
Re: Is bool no longer a primitive data type of C/C++ ? olcott <NoOne@NoWhere.com> - 2020-11-02 12:17 -0600
Re: Is bool no longer a primitive data type of C/C++ ? James Kuyper <jameskuyper@alumni.caltech.edu> - 2020-11-02 14:03 -0500
Re: Is bool no longer a primitive data type of C/C++ ? olcott <NoOne@NoWhere.com> - 2020-11-02 13:05 -0600
Re: Is bool no longer a primitive data type of C/C++ ? Mike Terry <news.dead.person.stones@darjeeling.plus.com> - 2020-11-02 16:50 +0000
Re: Is bool no longer a primitive data type of C/C++ ? olcott <NoOne@NoWhere.com> - 2020-11-02 11:07 -0600
Re: Is bool no longer a primitive data type of C/C++ ? Bonita Montero <Bonita.Montero@gmail.com> - 2020-11-02 18:08 +0100
Re: Is bool no longer a primitive data type of C/C++ ? olcott <NoOne@NoWhere.com> - 2020-11-02 11:11 -0600
Re: Is bool no longer a primitive data type of C/C++ ? Bonita Montero <Bonita.Montero@gmail.com> - 2020-11-02 18:13 +0100
Re: Is bool no longer a primitive data type of C/C++ ? olcott <NoOne@NoWhere.com> - 2020-11-02 11:25 -0600
Re: Is bool no longer a primitive data type of C/C++ ? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2020-11-02 17:22 +0000
Re: Is bool no longer a primitive data type of C/C++ ? olcott <NoOne@NoWhere.com> - 2020-11-02 11:26 -0600
Re: Is bool no longer a primitive data type of C/C++ ? olcott <NoOne@NoWhere.com> - 2020-11-02 11:38 -0600
Re: Is bool no longer a primitive data type of C/C++ ? Bonita Montero <Bonita.Montero@gmail.com> - 2020-11-02 19:01 +0100
Re: Is bool no longer a primitive data type of C/C++ ? olcott <NoOne@NoWhere.com> - 2020-11-02 12:19 -0600
Re: Is bool no longer a primitive data type of C/C++ ? "james...@alumni.caltech.edu" <jameskuyper@alumni.caltech.edu> - 2020-11-02 12:19 -0800
Re: Is bool no longer a primitive data type of C/C++ ? Tim Rentsch <tr.17687@z991.linuxsc.com> - 2020-11-29 00:09 -0800
Re: Is bool no longer a primitive data type of C/C++ ? David Brown <david.brown@hesbynett.no> - 2020-11-29 13:41 +0100
Re: Is bool no longer a primitive data type of C/C++ ? Richard Damon <Richard@Damon-Family.org> - 2020-11-02 13:18 -0500
Re: Is bool no longer a primitive data type of C/C++ ? olcott <NoOne@NoWhere.com> - 2020-11-02 13:06 -0600
Re: Is bool no longer a primitive data type of C/C++ ? "james...@alumni.caltech.edu" <jameskuyper@alumni.caltech.edu> - 2020-11-02 11:18 -0800
Re: Is bool no longer a primitive data type of C/C++ ? olcott <NoOne@NoWhere.com> - 2020-11-02 13:42 -0600
Re: Is bool no longer a primitive data type of C/C++ ? "james...@alumni.caltech.edu" <jameskuyper@alumni.caltech.edu> - 2020-11-02 12:39 -0800
Re: Is bool no longer a primitive data type of C/C++ ? olcott <NoOne@NoWhere.com> - 2020-11-02 15:08 -0600
Re: Is bool no longer a primitive data type of C/C++ ? Tim Rentsch <tr.17687@z991.linuxsc.com> - 2020-11-29 00:14 -0800
Re: Is bool no longer a primitive data type of C/C++ ? David Brown <david.brown@hesbynett.no> - 2020-11-29 13:53 +0100
Re: Is bool no longer a primitive data type of C/C++ ? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2020-11-29 13:18 +0000
Re: Is bool no longer a primitive data type of C/C++ ? David Brown <david.brown@hesbynett.no> - 2020-11-29 16:16 +0100
Re: Is bool no longer a primitive data type of C/C++ ? Tim Rentsch <tr.17687@z991.linuxsc.com> - 2020-11-29 17:53 -0800
Re: Is bool no longer a primitive data type of C/C++ ? Richard Damon <Richard@Damon-Family.org> - 2020-11-29 08:19 -0500
Re: Is bool no longer a primitive data type of C/C++ ? Tim Rentsch <tr.17687@z991.linuxsc.com> - 2020-11-29 17:42 -0800
Re: Is bool no longer a primitive data type of C/C++ ? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2020-11-02 20:42 +0000
Re: Is bool no longer a primitive data type of C/C++ ? olcott <NoOne@NoWhere.com> - 2020-11-02 15:15 -0600
Re: Is bool no longer a primitive data type of C/C++ ? David Brown <david.brown@hesbynett.no> - 2020-11-02 23:04 +0100
Re: Is bool no longer a primitive data type of C/C++ ? olcott <NoOne@NoWhere.com> - 2020-11-02 16:24 -0600
Re: Is bool no longer a primitive data type of C/C++ ? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2020-11-02 22:40 +0000
Re: Is bool no longer a primitive data type of C/C++ ? Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2020-11-02 16:23 -0800
Re: Is bool no longer a primitive data type of C/C++ ? olcott <NoOne@NoWhere.com> - 2020-11-02 17:32 -0600
Re: Is bool no longer a primitive data type of C/C++ ? David Brown <david.brown@hesbynett.no> - 2020-11-02 23:02 +0100
Re: Is bool no longer a primitive data type of C/C++ ? Joe Pfeiffer <pfeiffer@cs.nmsu.edu> - 2020-11-02 09:56 -0700
Re: Is bool no longer a primitive data type of C/C++ ? Bonita Montero <Bonita.Montero@gmail.com> - 2020-11-02 18:05 +0100
Re: Is bool no longer a primitive data type of C/C++ ? olcott <NoOne@NoWhere.com> - 2020-11-02 11:08 -0600
Re: Is bool no longer a primitive data type of C/C++ ? Bonita Montero <Bonita.Montero@gmail.com> - 2020-11-02 18:14 +0100
Re: Is bool no longer a primitive data type of C/C++ ? olcott <NoOne@NoWhere.com> - 2020-11-02 12:17 -0600
Re: Is bool no longer a primitive data type of C/C++ ? David Brown <david.brown@hesbynett.no> - 2020-11-02 22:41 +0100
Re: Is bool no longer a primitive data type of C/C++ ? David Brown <david.brown@hesbynett.no> - 2020-11-02 22:48 +0100
Re: Is bool no longer a primitive data type of C/C++ ? Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2020-11-02 16:05 -0800
Re: Is bool no longer a primitive data type of C/C++ ? olcott <NoOne@NoWhere.com> - 2020-11-02 18:45 -0600
Re: Is bool no longer a primitive data type of C/C++ ? David Brown <david.brown@hesbynett.no> - 2020-11-03 11:35 +0100
Why macro ? Bonita Montero <Bonita.Montero@gmail.com> - 2020-11-02 19:03 +0100
Re: Why macro ? scott@slp53.sl.home (Scott Lurndal) - 2020-11-02 19:05 +0000
Re: Why macro ? Bonita Montero <Bonita.Montero@gmail.com> - 2020-11-03 07:41 +0100
Re: Why macro ? David Brown <david.brown@hesbynett.no> - 2020-11-03 11:38 +0100
Re: Why macro ? Bonita Montero <Bonita.Montero@gmail.com> - 2020-11-03 12:39 +0100
Re: Why macro ? David Brown <david.brown@hesbynett.no> - 2020-11-03 13:10 +0100
Re: Why macro ? Bonita Montero <Bonita.Montero@gmail.com> - 2020-11-03 13:23 +0100
Re: Why macro ? Bo Persson <bo@bo-persson.se> - 2020-11-03 13:45 +0100
Re: Why macro ? Bonita Montero <Bonita.Montero@gmail.com> - 2020-11-03 14:26 +0100
Re: Why macro ? Malcolm McLean <malcolm.arthur.mclean@gmail.com> - 2020-11-03 05:46 -0800
Re: Why macro ? Bonita Montero <Bonita.Montero@gmail.com> - 2020-11-03 15:10 +0100
Re: Why macro ? David Brown <david.brown@hesbynett.no> - 2020-11-03 15:49 +0100
Re: Why macro ? Bonita Montero <Bonita.Montero@gmail.com> - 2020-11-03 15:56 +0100
Re: Why macro ? David Brown <david.brown@hesbynett.no> - 2020-11-03 17:25 +0100
Re: Why macro ? Bonita Montero <Bonita.Montero@gmail.com> - 2020-11-03 17:29 +0100
Re: Why macro ? scott@slp53.sl.home (Scott Lurndal) - 2020-11-03 17:12 +0000
Re: Why macro ? Bonita Montero <Bonita.Montero@gmail.com> - 2020-11-03 18:15 +0100
Re: Why macro ? red floyd <no.spam.here@its.invalid> - 2020-11-04 07:12 -0800
Re: Why macro ? Bonita Montero <Bonita.Montero@gmail.com> - 2020-11-04 16:33 +0100
Re: Why macro ? Malcolm McLean <malcolm.arthur.mclean@gmail.com> - 2020-11-03 09:22 -0800
Re: Why macro ? Bart <bc@freeuk.com> - 2020-11-03 17:13 +0000
Re: Why macro ? David Brown <david.brown@hesbynett.no> - 2020-11-03 20:07 +0100
Re: Why macro ? Juha Nieminen <nospam@thanks.invalid> - 2020-11-04 13:41 +0000
Re: Why macro ? Juha Nieminen <nospam@thanks.invalid> - 2020-11-04 13:32 +0000
Re: Why macro ? Richard Damon <Richard@Damon-Family.org> - 2020-11-04 08:59 -0500
Re: Why macro ? Malcolm McLean <malcolm.arthur.mclean@gmail.com> - 2020-11-04 06:01 -0800
Re: Why macro ? Sjouke Burry <burrynulnulfour@ppllaanneett.nnll> - 2020-11-04 17:11 +0100
Re: Why macro ? Richard Damon <Richard@Damon-Family.org> - 2020-11-04 20:33 -0500
Re: Why macro ? David Brown <david.brown@hesbynett.no> - 2020-11-04 16:44 +0100
Re: Why macro ? Richard Damon <Richard@Damon-Family.org> - 2020-11-03 12:37 -0500
Re: Why macro ? Malcolm McLean <malcolm.arthur.mclean@gmail.com> - 2020-11-03 10:42 -0800
Re: Why macro ? scott@slp53.sl.home (Scott Lurndal) - 2020-11-03 19:43 +0000
Re: Why macro ? David Brown <david.brown@hesbynett.no> - 2020-11-04 09:20 +0100
Re: Why macro ? Malcolm McLean <malcolm.arthur.mclean@gmail.com> - 2020-11-03 03:07 -0800
Re: Why macro ? Bonita Montero <Bonita.Montero@gmail.com> - 2020-11-03 12:40 +0100
Re: Why macro ? Malcolm McLean <malcolm.arthur.mclean@gmail.com> - 2020-11-03 04:02 -0800
Re: Is bool no longer a primitive data type of C/C++ ? megonsara11@gmail.com - 2020-11-06 20:37 -0800
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