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Groups > comp.lang.c > #101142
| From | Keith Thompson <kst-u@mib.org> |
|---|---|
| Newsgroups | comp.lang.c |
| Subject | Re: lvalues from the ternary op |
| Date | 2017-01-04 14:20 -0800 |
| Organization | None to speak of |
| Message-ID | <lninpusbzq.fsf@kst-u.example.com> (permalink) |
| References | (3 earlier) <8737klapvv.fsf@bsb.me.uk> <o4jftg$vqf$1@gioia.aioe.org> <877f6alefh.fsf@bsb.me.uk> <lntw9esdh5.fsf@kst-u.example.com> <ed5a0lF11foU2@mid.individual.net> |
Ian Collins <ian-news@hotmail.com> writes:
> On 01/ 5/17 10:48 AM, Keith Thompson wrote:
>> Ben Bacarisse <ben.usenet@bsb.me.uk> writes:
>> [...]
>>> But I don't think that gets us any closer to knowing what might or might
>>> not be "reasonable" in C. The C standard enumerates all the expression
>>> forms that are lvalues and, as in the case of x.y for example, it
>>> sometimes depends on whether one or other part of the expression is
>>> itself an lvalue. So there's no obvious reason that it could not say
>>> that a conditional expression is an lvalue if both arms are lvalue
>>> expressions.
>>
>> And of the same type, or perhaps compatible types would be sufficient.
>>
>> For example, this:
>>
>> int x;
>> double y;
>> (condition ? x : y) = 42;
>>
>> would be difficult to implement sensibly. Taking the address of a
>> ternary expression would be even more difficult. (C++ already does
>> this; I haven't checked the standard's wording.)
>
> Does it?
Perhaps "does this" was ambiguous. What I meant is that in C++, given:
int i1, i2;
double x;
(condition ? i1 : i2) is an lvalue, but (condition ? i1 : x) is not.
I verified this by compiling a couple of small test programs (with
a ternary expression on the LHS of an assignment) with g++.
--
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"
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Re: lvalues from the ternary op Manfred <noname@invalid.add> - 2017-01-04 19:46 +0100
Re: lvalues from the ternary op supercat@casperkitty.com - 2017-01-04 11:08 -0800
Re: lvalues from the ternary op Ben Bacarisse <ben.usenet@bsb.me.uk> - 2017-01-04 21:10 +0000
Re: lvalues from the ternary op Keith Thompson <kst-u@mib.org> - 2017-01-04 13:48 -0800
Re: lvalues from the ternary op Ian Collins <ian-news@hotmail.com> - 2017-01-05 11:07 +1300
Re: lvalues from the ternary op Keith Thompson <kst-u@mib.org> - 2017-01-04 14:20 -0800
Re: lvalues from the ternary op supercat@casperkitty.com - 2017-01-04 14:41 -0800
Re: lvalues from the ternary op Keith Thompson <kst-u@mib.org> - 2017-01-04 15:21 -0800
Re: lvalues from the ternary op supercat@casperkitty.com - 2017-01-04 15:52 -0800
Re: lvalues from the ternary op Keith Thompson <kst-u@mib.org> - 2017-01-04 16:37 -0800
Re: lvalues from the ternary op Keith Thompson <kst-u@mib.org> - 2017-01-04 18:31 -0800
Re: lvalues from the ternary op Tim Rentsch <txr@alumni.caltech.edu> - 2017-01-13 17:26 -0800
Re: lvalues from the ternary op Keith Thompson <kst-u@mib.org> - 2017-01-13 17:49 -0800
Re: lvalues from the ternary op Tim Rentsch <txr@alumni.caltech.edu> - 2017-01-15 22:53 -0800
Re: lvalues from the ternary op Tim Rentsch <txr@alumni.caltech.edu> - 2017-01-13 17:08 -0800
Re: lvalues from the ternary op Ben Bacarisse <ben.usenet@bsb.me.uk> - 2017-01-14 02:15 +0000
Re: lvalues from the ternary op Tim Rentsch <txr@alumni.caltech.edu> - 2017-01-15 22:51 -0800
Re: lvalues from the ternary op luser droog <luser.droog@gmail.com> - 2017-01-16 23:09 -0800
Re: lvalues from the ternary op Manfred <noname@invalid.add> - 2017-01-18 14:51 +0100
Re: lvalues from the ternary op Keith Thompson <kst-u@mib.org> - 2017-01-18 09:59 -0800
Re: lvalues from the ternary op Lew Pitcher <lew.pitcher@digitalfreehold.ca> - 2017-01-18 13:12 -0500
Re: lvalues from the ternary op supercat@casperkitty.com - 2017-01-18 12:11 -0800
Re: lvalues from the ternary op Keith Thompson <kst-u@mib.org> - 2017-01-18 12:45 -0800
Re: lvalues from the ternary op supercat@casperkitty.com - 2017-01-18 14:07 -0800
Re: lvalues from the ternary op Keith Thompson <kst-u@mib.org> - 2017-01-18 14:40 -0800
Re: lvalues from the ternary op supercat@casperkitty.com - 2017-01-18 16:10 -0800
Re: lvalues from the ternary op Keith Thompson <kst-u@mib.org> - 2017-01-18 18:08 -0800
Re: lvalues from the ternary op supercat@casperkitty.com - 2017-01-19 06:44 -0800
Re: lvalues from the ternary op Keith Thompson <kst-u@mib.org> - 2017-01-19 08:40 -0800
Re: lvalues from the ternary op supercat@casperkitty.com - 2017-01-19 12:32 -0800
Re: lvalues from the ternary op supercat@casperkitty.com - 2017-01-20 06:01 -0800
Re: lvalues from the ternary op Keith Thompson <kst-u@mib.org> - 2017-01-20 08:15 -0800
Re: lvalues from the ternary op supercat@casperkitty.com - 2017-01-20 10:51 -0800
Re: lvalues from the ternary op Keith Thompson <kst-u@mib.org> - 2017-01-20 11:32 -0800
Re: lvalues from the ternary op supercat@casperkitty.com - 2017-01-20 13:41 -0800
Re: lvalues from the ternary op supercat@casperkitty.com - 2017-01-23 07:04 -0800
Re: lvalues from the ternary op Ike Naar <ike@iceland.freeshell.org> - 2017-01-23 17:59 +0000
Re: lvalues from the ternary op supercat@casperkitty.com - 2017-01-23 10:57 -0800
Re: lvalues from the ternary op Tim Rentsch <txr@alumni.caltech.edu> - 2017-01-31 08:45 -0800
Re: lvalues from the ternary op Keith Thompson <kst-u@mib.org> - 2017-01-31 09:13 -0800
Re: lvalues from the ternary op supercat@casperkitty.com - 2017-01-31 10:17 -0800
Re: lvalues from the ternary op Ben Bacarisse <ben.usenet@bsb.me.uk> - 2017-02-01 01:51 +0000
Re: lvalues from the ternary op supercat@casperkitty.com - 2017-02-01 14:24 -0800
Re: lvalues from the ternary op Ben Bacarisse <ben.usenet@bsb.me.uk> - 2017-02-02 03:07 +0000
Re: lvalues from the ternary op Tim Rentsch <txr@alumni.caltech.edu> - 2017-02-04 04:43 -0800
Re: lvalues from the ternary op supercat@casperkitty.com - 2017-02-04 08:01 -0800
Re: lvalues from the ternary op Tim Rentsch <txr@alumni.caltech.edu> - 2017-02-09 09:06 -0800
Re: lvalues from the ternary op supercat@casperkitty.com - 2017-02-09 11:56 -0800
Re: lvalues from the ternary op Tim Rentsch <txr@alumni.caltech.edu> - 2017-02-12 10:29 -0800
Re: lvalues from the ternary op supercat@casperkitty.com - 2017-02-12 13:43 -0800
Re: lvalues from the ternary op Tim Rentsch <txr@alumni.caltech.edu> - 2017-02-19 21:44 -0800
Re: lvalues from the ternary op supercat@casperkitty.com - 2017-02-20 08:15 -0800
Re: lvalues from the ternary op Tim Rentsch <txr@alumni.caltech.edu> - 2017-02-24 07:58 -0800
Re: lvalues from the ternary op supercat@casperkitty.com - 2017-02-24 10:00 -0800
Re: lvalues from the ternary op scott@slp53.sl.home (Scott Lurndal) - 2017-02-24 18:58 +0000
Re: lvalues from the ternary op supercat@casperkitty.com - 2017-02-24 13:03 -0800
Re: lvalues from the ternary op Keith Thompson <kst-u@mib.org> - 2017-02-24 14:11 -0800
Re: lvalues from the ternary op Keith Thompson <kst-u@mib.org> - 2017-02-24 12:42 -0800
Re: lvalues from the ternary op Keith Thompson <kst-u@mib.org> - 2017-02-24 13:49 -0800
Re: lvalues from the ternary op supercat@casperkitty.com - 2017-02-24 13:58 -0800
Re: lvalues from the ternary op Keith Thompson <kst-u@mib.org> - 2017-02-24 14:56 -0800
Re: lvalues from the ternary op supercat <flatfinger@casperkitty.com> - 2017-02-25 14:00 -0800
Re: lvalues from the ternary op Tim Rentsch <txr@alumni.caltech.edu> - 2017-02-25 09:23 -0800
Re: lvalues from the ternary op Tim Rentsch <txr@alumni.caltech.edu> - 2017-02-25 09:43 -0800
Re: lvalues from the ternary op Kelsey Bjarnason <kbjarnason@gmail.com> - 2017-02-01 22:47 -0800
Re: lvalues from the ternary op supercat@casperkitty.com - 2017-02-02 10:12 -0800
Re: lvalues from the ternary op Tim Rentsch <txr@alumni.caltech.edu> - 2017-02-04 07:51 -0800
Re: lvalues from the ternary op supercat@casperkitty.com - 2017-02-04 08:18 -0800
Re: lvalues from the ternary op Tim Rentsch <txr@alumni.caltech.edu> - 2017-02-09 08:58 -0800
Re: lvalues from the ternary op Tim Rentsch <txr@alumni.caltech.edu> - 2017-02-04 04:00 -0800
Re: lvalues from the ternary op Kelsey Bjarnason <kbjarnason@gmail.com> - 2017-02-04 09:35 -0800
Re: lvalues from the ternary op Tim Rentsch <txr@alumni.caltech.edu> - 2017-02-04 09:35 -0800
Re: lvalues from the ternary op Robert Wessel <robertwessel2@yahoo.com> - 2017-01-31 13:36 -0600
Re: lvalues from the ternary op supercat@casperkitty.com - 2017-01-31 12:23 -0800
Re: lvalues from the ternary op Tim Rentsch <txr@alumni.caltech.edu> - 2017-02-01 13:48 -0800
Re: lvalues from the ternary op Tim Rentsch <txr@alumni.caltech.edu> - 2017-01-31 08:53 -0800
Re: lvalues from the ternary op Manfred <noname@invalid.add> - 2017-01-19 14:10 +0100
Re: lvalues from the ternary op Tim Rentsch <txr@alumni.caltech.edu> - 2017-01-30 12:05 -0800
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