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Re: Why does the -> operator exist ?

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Spiros Bousbouras <spibou@gmail.com> writes:

> On Tue, 27 Jun 2023 15:01:16 +0200
> felix@palmen-it.de (Felix Palmen) wrote:
>> * Spiros Bousbouras <spibou@gmail.com>:
>> > I mean would it create an ambiguity if you could write  s.field
>> > both when  s  is a structure or union and when  s  is a pointer
>> > to a structure or union ?
>> 
>> Most likely no.
>> 
>> So, my answer will be an opinion: In a language like C (with explicit
>> resource management), pointers (taking them, dereferencing them) really
>> *should* be explicit. For correct code, it's important to know whether
>> you're dealing with a pointer or not. And the compiler gets a chance to
>> tell you "careful, this doesn't have the type you seemed to expect".
>> 
>> Yes, I know there are already a few exceptions. But looking at function
>> pointers, they are special anyways, as functions themselves don't exist
>> as types. And looking at the special evaluation of an array identifier
>> as a pointer to its first element, well, this really created more than
>> enough confusion, especially among beginners.
>
> A more similar exception is an expression  a + b  where  b  is an integer
> type. a  can be a pointer or an arithmetic type.

This could have been outlawed and replaced by &a[b].  Of course,
currently, a[b] is defined as *(a+b) so it relies on pointer arithmetic,
but a[b] could have been defined independently so as to have a+b
generate a warning.  I don't think this was ever a consideration.

-- 
Ben.

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Thread

Why does the  ->  operator exist ? Spiros Bousbouras <spibou@gmail.com> - 2023-06-27 09:12 +0000
  Re: Why does the  ->  operator exist ? felix@palmen-it.de (Felix Palmen) - 2023-06-27 15:01 +0200
    Re: Why does the  ->  operator exist ? Spiros Bousbouras <spibou@gmail.com> - 2023-06-27 14:09 +0000
      Re: Why does the  ->  operator exist ? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2023-06-27 15:56 +0100
  Re: Why does the -> operator exist ? Bart <bc@freeuk.com> - 2023-06-27 16:06 +0100
    Re: Why does the -> operator exist ? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2023-06-27 18:01 +0100
      Re: Why does the -> operator exist ? BGB <cr88192@gmail.com> - 2023-06-27 12:46 -0500
    Re: Why does the -> operator exist ? fir <profesor.fir@gmail.com> - 2023-08-09 00:08 -0700
      Re: Why does the -> operator exist ? fir <profesor.fir@gmail.com> - 2023-08-09 00:11 -0700
        Re: Why does the -> operator exist ? fir <profesor.fir@gmail.com> - 2023-08-09 00:23 -0700
  Re: Why does the  ->  operator exist ? Lew Pitcher <lew.pitcher@digitalfreehold.ca> - 2023-06-27 15:13 +0000
  Re: Why does the  ->  operator exist ? Kaz Kylheku <864-117-4973@kylheku.com> - 2023-06-27 15:30 +0000
    Re: Why does the -> operator exist ? Bart <bc@freeuk.com> - 2023-06-27 17:05 +0100
      Re: Why does the -> operator exist ? Kaz Kylheku <864-117-4973@kylheku.com> - 2023-06-27 17:11 +0000
  Re: Why does the -> operator exist ? BGB <cr88192@gmail.com> - 2023-06-27 10:54 -0500
  Re: Why does the  ->  operator exist ? Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2023-06-27 12:23 -0700
    Re: Why does the  ->  operator exist ? Joe Pfeiffer <pfeiffer@cs.nmsu.edu> - 2023-06-27 15:33 -0600
    Re: Why does the  ->  operator exist ? Spiros Bousbouras <spibou@gmail.com> - 2023-06-28 16:31 +0000
      Re: Why does the  ->  operator exist ? Kaz Kylheku <864-117-4973@kylheku.com> - 2023-06-29 03:14 +0000
    Re: Why does the  ->  operator exist ? Tim Rentsch <tr.17687@z991.linuxsc.com> - 2023-07-20 18:57 -0700
      Re: Why does the  ->  operator exist ? Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2023-07-20 19:49 -0700
        Re: Why does the  ->  operator exist ? Tim Rentsch <tr.17687@z991.linuxsc.com> - 2023-08-08 05:49 -0700
          Re: Why does the  ->  operator exist ? Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2023-08-08 16:33 -0700
            Re: Why does the  ->  operator exist ? Tim Rentsch <tr.17687@z991.linuxsc.com> - 2023-08-14 04:34 -0700
              I love it... (Was: Why does the  ->  operator exist ?) gazelle@shell.xmission.com (Kenny McCormack) - 2023-08-14 12:41 +0000
              Re: Why does the  ->  operator exist ? Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2023-08-14 15:10 -0700
                Re: Why does the  ->  operator exist ? Phil Carmody <pc+usenet@asdf.org> - 2023-08-15 23:00 +0300
                Re: Why does the  ->  operator exist ? Tim Rentsch <tr.17687@z991.linuxsc.com> - 2023-08-16 05:29 -0700
      Re: Why does the  ->  operator exist ? Kaz Kylheku <864-117-4973@kylheku.com> - 2023-07-22 05:39 +0000
  Re: Why does the -> operator exist ? Andrey Tarasevich <andreytarasevich@hotmail.com> - 2023-06-28 14:16 -0700

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