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Groups > comp.lang.c > #147680
| From | David Brown <david.brown@hesbynett.no> |
|---|---|
| Newsgroups | comp.lang.c |
| Subject | Re: Is this kosher wrt Generic? |
| Date | 2019-11-06 22:45 +0100 |
| Organization | A noiseless patient Spider |
| Message-ID | <qpvett$drj$1@dont-email.me> (permalink) |
| References | (2 earlier) <qptpoa$6a4$1@gioia.aioe.org> <8f6ba3a5-3385-45f8-bfc6-342f6cbd54d4@googlegroups.com> <5e3b0d5e-5e2c-4acd-8111-346e859e3e51@googlegroups.com> <7c6d2fae-86af-4660-932a-64bccef28b4a@googlegroups.com> <qKAwF.44683$vV6.25665@fx17.am4> |
On 06/11/2019 15:26, Bart wrote:
> On 06/11/2019 13:56, Thiago Adams wrote:
>> On Wednesday, November 6, 2019 at 10:33:11 AM UTC-3, Thiago Adams wrote:
>>> Option 2: With restrict signature.
>>> In this case we need a declaration for the 'interface' for foo.
>>> for instance, one name/concept that I would like to use for any
>>> type is destroy. All function destroy have the same signature.
>>>
>>> So the generic interface for destroy could be:
>>>
>>> void destroy(auto);
>>>
>>> and the implementation.
>>>
>>> void x_destroy(struct X* p) : destroy;
>>>
>>> the implementation must follow the destroy contract.
>> ...
>>
>>
>> This feature with contract is similar of some C++ operator
>> overloading.
>>
>> Some operators in C++ have strict contracts. For instance,
>> the operator delete must be:
>>
>> void operator delete(void * p)
>>
>> if I change the return type for instance:
>>
>> void* operator delete(void * p)
>> error: ‘operator delete’ must return type ‘void’
>>
>>
>> In my view, destroy, init, delete , new, swap, clone etc..
>> are 'universal operators', just like + , - 0 and they could exist by
>> default in the C language using this feature of function tags.
>>
>> Not only this, but some algorithms are just a matter of
>> composition and destroy and init are samples of that.
>> In this case the language could generate these operators for
>> us by composition.
>>
>> If we think in terms of sqrt we don't want function overloading
>> with zero or more than one argument.
>> In this aspect _Generic has advantages over function overloading
>> where anything is possible.
>
> I haven't tried function overloading (where you have to look at all
> combinations of parameter and return types to choose the right function,
> and there might still be ambiguities).
>
> Class-based (or method-based) is simpler, and the choice is made on the
> first parameter only. Take this example in fantasy C:
>
> typedef struct {
> void SayMyName(bart &s) {puts("Bart");}
> } bart;
>
> typedef struct {
> void SayMyName(lisa &s) {puts("Lisa");}
> } lisa;
>
> bart B;
> lisa L;
>
> B.SayMyName(); // Bart
> L.SayMyName(); // Lisa
>
> bart.SayMyName(B); // Bart
> lisa.SayMyName(L); // Lisa
You can get a fair amount of that today in C, though it is a little more
verbose:
#include <stdio.h>
typedef struct bart {
void (*SayMyName)(struct bart*);
} bart;
void bart_SayMyName(struct bart* s) { puts("Bart"); }
#define bart_init { bart_SayMyName }
typedef struct lisa {
void (*SayMyName)(struct lisa*);
} lisa;
void lisa_SayMyName(struct lisa * s) { puts("Lisa"); }
#define lisa_init { lisa_SayMyName }
bart B = bart_init;
lisa L = lisa_init;
void foo(void) {
B.SayMyName(&B);
L.SayMyName(&L);
bart_SayMyName(&B);
lisa_SayMyName(&L);
}
Not perfect, but some people find such constructs useful.
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Is this kosher wrt Generic? "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2019-11-04 22:55 -0800
Re: Is this kosher wrt Generic? Bonita Montero <Bonita.Montero@gmail.com> - 2019-11-05 08:12 +0100
Re: Is this kosher wrt Generic? Thiago Adams <thiago.adams@gmail.com> - 2019-11-05 03:52 -0800
Re: Is this kosher wrt Generic? Bonita Montero <Bonita.Montero@gmail.com> - 2019-11-05 13:12 +0100
Re: Is this kosher wrt Generic? Thiago Adams <thiago.adams@gmail.com> - 2019-11-05 04:24 -0800
Re: Is this kosher wrt Generic? Bonita Montero <Bonita.Montero@gmail.com> - 2019-11-05 13:33 +0100
Re: Is this kosher wrt Generic? Thiago Adams <thiago.adams@gmail.com> - 2019-11-05 04:57 -0800
Re: Is this kosher wrt Generic? Bonita Montero <Bonita.Montero@gmail.com> - 2019-11-05 14:08 +0100
Re: Is this kosher wrt Generic? Thiago Adams <thiago.adams@gmail.com> - 2019-11-05 05:21 -0800
Re: Is this kosher wrt Generic? Bonita Montero <Bonita.Montero@gmail.com> - 2019-11-05 14:27 +0100
Re: Is this kosher wrt Generic? Thiago Adams <thiago.adams@gmail.com> - 2019-11-05 05:42 -0800
Re: Is this kosher wrt Generic? Bonita Montero <Bonita.Montero@gmail.com> - 2019-11-05 14:51 +0100
Re: Is this kosher wrt Generic? Bart <bc@freeuk.com> - 2019-11-05 14:49 +0000
Re: Is this kosher wrt Generic? Bonita Montero <Bonita.Montero@gmail.com> - 2019-11-05 15:53 +0100
Re: Is this kosher wrt Generic? Bart <bc@freeuk.com> - 2019-11-05 15:59 +0000
Re: Is this kosher wrt Generic? Bonita Montero <Bonita.Montero@gmail.com> - 2019-11-05 17:11 +0100
Re: Is this kosher wrt Generic? Malcolm McLean <malcolm.arthur.mclean@gmail.com> - 2019-11-05 09:19 -0800
Re: Is this kosher wrt Generic? Malcolm McLean <malcolm.arthur.mclean@gmail.com> - 2019-11-05 07:00 -0800
Re: Is this kosher wrt Generic? David Brown <david.brown@hesbynett.no> - 2019-11-05 16:30 +0100
Re: Is this kosher wrt Generic? Bonita Montero <Bonita.Montero@gmail.com> - 2019-11-05 15:31 +0100
Re: Is this kosher wrt Generic? Ian Collins <ian-news@hotmail.com> - 2019-11-06 10:34 +1300
Re: Is this kosher wrt Generic? Bart <bc@freeuk.com> - 2019-11-05 22:16 +0000
Re: Is this kosher wrt Generic? Ian Collins <ian-news@hotmail.com> - 2019-11-06 11:34 +1300
Re: Is this kosher wrt Generic? Bart <bc@freeuk.com> - 2019-11-05 23:12 +0000
Re: Is this kosher wrt Generic? Ian Collins <ian-news@hotmail.com> - 2019-11-06 12:29 +1300
Re: Is this kosher wrt Generic? David Brown <david.brown@hesbynett.no> - 2019-11-06 10:17 +0100
Re: Is this kosher wrt Generic? Bonita Montero <Bonita.Montero@gmail.com> - 2019-11-06 10:56 +0100
Re: Is this kosher wrt Generic? Bonita Montero <Bonita.Montero@gmail.com> - 2019-11-06 10:02 +0100
Re: Is this kosher wrt Generic? Bart <bc@freeuk.com> - 2019-11-06 10:43 +0000
Re: Is this kosher wrt Generic? Thiago Adams <thiago.adams@gmail.com> - 2019-11-06 04:56 -0800
Re: Is this kosher wrt Generic? Bonita Montero <Bonita.Montero@gmail.com> - 2019-11-06 14:05 +0100
Re: Is this kosher wrt Generic? Tim Rentsch <tr.17687@z991.linuxsc.com> - 2019-11-08 21:03 -0800
Re: Is this kosher wrt Generic? Ian Collins <ian-news@hotmail.com> - 2019-11-10 08:45 +1300
Re: Is this kosher wrt Generic? Tim Rentsch <tr.17687@z991.linuxsc.com> - 2019-11-28 16:35 -0800
Re: Is this kosher wrt Generic? David Brown <david.brown@hesbynett.no> - 2019-11-29 12:41 +0100
Re: Is this kosher wrt Generic? Thiago Adams <thiago.adams@gmail.com> - 2019-11-29 04:08 -0800
Re: Is this kosher wrt Generic? Bart <bc@freeuk.com> - 2019-11-29 13:01 +0000
Re: Is this kosher wrt Generic? Thiago Adams <thiago.adams@gmail.com> - 2019-11-29 06:43 -0800
Re: Is this kosher wrt Generic? Bart <bc@freeuk.com> - 2019-11-29 17:31 +0000
Re: Is this kosher wrt Generic? David Brown <david.brown@hesbynett.no> - 2019-11-29 14:31 +0100
Re: Is this kosher wrt Generic? Öö Tiib <ootiib@hot.ee> - 2019-11-30 13:16 -0800
Re: Is this kosher wrt Generic? Thiago Adams <thiago.adams@gmail.com> - 2019-12-02 03:31 -0800
Re: Is this kosher wrt Generic? Öö Tiib <ootiib@hot.ee> - 2019-12-02 23:30 -0800
Re: Is this kosher wrt Generic? Ian Collins <ian-news@hotmail.com> - 2019-12-01 12:10 +1300
Re: Is this kosher wrt Generic? Tim Rentsch <tr.17687@z991.linuxsc.com> - 2020-01-11 09:35 -0800
Re: Is this kosher wrt Generic? Jorgen Grahn <grahn+nntp@snipabacken.se> - 2019-11-05 22:49 +0000
Re: Is this kosher wrt Generic? Thiago Adams <thiago.adams@gmail.com> - 2019-11-05 05:12 -0800
Re: Is this kosher wrt Generic? Bonita Montero <Bonita.Montero@gmail.com> - 2019-11-05 14:20 +0100
Re: Is this kosher wrt Generic? guinness.tony@gmail.com - 2019-11-05 16:19 -0800
Re: Is this kosher wrt Generic? "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2019-11-06 00:06 -0800
Re: Is this kosher wrt Generic? Thiago Adams <thiago.adams@gmail.com> - 2019-11-05 03:19 -0800
Re: Is this kosher wrt Generic? "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2019-11-05 22:38 -0800
Re: Is this kosher wrt Generic? Thiago Adams <thiago.adams@gmail.com> - 2019-11-06 04:50 -0800
Re: Is this kosher wrt Generic? Thiago Adams <thiago.adams@gmail.com> - 2019-11-06 05:32 -0800
Re: Is this kosher wrt Generic? Thiago Adams <thiago.adams@gmail.com> - 2019-11-06 05:56 -0800
Re: Is this kosher wrt Generic? Bart <bc@freeuk.com> - 2019-11-06 14:26 +0000
Re: Is this kosher wrt Generic? Thiago Adams <thiago.adams@gmail.com> - 2019-11-06 09:04 -0800
Re: Is this kosher wrt Generic? David Brown <david.brown@hesbynett.no> - 2019-11-06 22:45 +0100
Re: Is this kosher wrt Generic? "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2019-11-29 14:35 -0800
Re: Is this kosher wrt Generic? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2019-11-29 23:23 +0000
Re: Is this kosher wrt Generic? "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2019-11-29 19:08 -0800
Re: Is this kosher wrt Generic? "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2019-11-29 19:12 -0800
Re: Is this kosher wrt Generic? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2019-11-30 10:44 +0000
Re: Is this kosher wrt Generic? "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2019-11-09 23:21 -0800
Re: Is this kosher wrt Generic? "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2019-11-09 23:22 -0800
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