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Re: NULL versus 0

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On 2021-09-26 at 09:47, Branimir Maksimovic wrote:
> On 2021-09-26, Jorgen Grahn <grahn+nntp@snipabacken.se> wrote:
>> On Sat, 2021-09-25, see.my....@gmail.com wrote:
>>>> int *pInt = 0;
>>>>
>>>> Nothing inherently wrong with that, but in C, it would be more
>>>> traditional to use NULL.
>>>
>>> It would be more traditional in C++, as well.
>>
>> Opinions varied.  Before nullptr, I always used NULL in C and 0 in
>> C++.  IIRC using 0 was a common recommendation here, too, for whatever
>> reason.
> 
> #define NULL (void*)0
> simple, problem is that in C++, one have to cast from void
> and that does not works, and this is BuG in C++.
> 
> 
  It is not a bug when it is done very much on purpose.

Stroustrup says:

"A pointer to any type of object can be assigned to a variable of type 
void*, a void* can be assigned to another void*, void* can be compared 
for equality and inequality, and a void* can be explicitly converted to 
another type. Other operations would be unsafe because the compiler 
cannot know what kind of object is really pointed to. Consequently, 
other operations result in compile-time errors."

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NULL versus 0 "das...@gmail.com" <dashley@gmail.com> - 2021-09-25 11:03 -0700
  Re: NULL versus 0 Branimir Maksimovic <branimir.maksimovic@gmail.com> - 2021-09-25 18:16 +0000
  Re: NULL versus 0 Paavo Helde <myfirstname@osa.pri.ee> - 2021-09-25 21:20 +0300
    Re: NULL versus 0 Paavo Helde <myfirstname@osa.pri.ee> - 2021-09-25 21:32 +0300
      Re: NULL versus 0 "das...@gmail.com" <dashley@gmail.com> - 2021-09-25 12:08 -0700
    Re: NULL versus 0 Juha Nieminen <nospam@thanks.invalid> - 2021-09-27 05:47 +0000
      Re: NULL versus 0 Bo Persson <bo@bo-persson.se> - 2021-09-27 08:32 +0200
        Re: NULL versus 0 "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2021-09-26 23:37 -0700
        Re: NULL versus 0 "Alf P. Steinbach" <alf.p.steinbach@gmail.com> - 2021-09-27 10:32 +0200
          Re: NULL versus 0 Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2021-09-27 11:32 -0700
      Re: NULL versus 0 James Kuyper <jameskuyper@alumni.caltech.edu> - 2021-09-27 15:03 -0400
  Re: NULL versus 0 "see.my....@gmail.com" <see.my.homepage@gmail.com> - 2021-09-25 13:05 -0700
    Re: NULL versus 0 Jorgen Grahn <grahn+nntp@snipabacken.se> - 2021-09-26 06:58 +0000
      Re: NULL versus 0 Branimir Maksimovic <branimir.maksimovic@gmail.com> - 2021-09-26 07:47 +0000
        Re: NULL versus 0 Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2021-09-26 02:15 -0700
          Re: NULL versus 0 Branimir Maksimovic <branimir.maksimovic@gmail.com> - 2021-09-26 09:38 +0000
            Re: NULL versus 0 Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2021-09-26 15:03 -0700
              Re: NULL versus 0 Branimir Maksimovic <branimir.maksimovic@gmail.com> - 2021-09-29 02:29 +0000
                Re: NULL versus 0 Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2021-09-28 20:34 -0700
                Re: NULL versus 0 David Brown <david.brown@hesbynett.no> - 2021-09-29 08:52 +0200
        Re: NULL versus 0 Bo Persson <bo@bo-persson.se> - 2021-09-26 13:54 +0200
          Re: NULL versus 0 Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2021-09-26 15:17 -0700
          Re: NULL versus 0 Branimir Maksimovic <branimir.maksimovic@gmail.com> - 2021-09-29 02:26 +0000
      Re: NULL versus 0 Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2021-09-26 02:17 -0700
      Re: NULL versus 0 HorseyWorsey@the_stables.com - 2021-09-26 14:20 +0000
  Re: NULL versus 0 James Kuyper <jameskuyper@alumni.caltech.edu> - 2021-09-25 17:36 -0400
  Re: NULL versus 0 "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2021-09-26 23:05 -0700

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