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From: James Kuyper <jameskuyper@alumni.caltech.edu>
Newsgroups: comp.lang.c
Subject: Re: question about nullptr
Date: Mon, 8 Jul 2024 11:03:42 -0400
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On 7/7/24 19:42, Ben Bacarisse wrote:
> scott@slp53.sl.home (Scott Lurndal) writes:
....
>> I.e. it can either be a null pointer or the value zero
>> depending on context, which makes it ambiguous to the casual
>> reader. Particularly when reading code that someone
>> else has written. NULL makes the programmers intent crystal
>> clear.
>
> That's a rather niche readership -- one that might consider
>
> char *p = 0;
>
> unclear. Do you want such people reading your C code with a view to
> working on it?


The problem is not "char p=0;". If you're sure what type p has, there's
no problem. The problem comes with code like "p=0", where "p=NULL" would
serve to remind you that p should be a pointer, while "p=nullptr"
guarantees a diagnostic if p is not a pointer. I have fixed bugs which
would have been caught a lot earlier if nullptr had existed, and had
been the only permitted kind of null pointer constant.