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From: Keith Thompson <kst-u@mib.org>
Newsgroups: comp.lang.c
Subject: Re: pointers
Date: Wed, 26 Oct 2016 09:05:51 -0700
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BartC <bc@freeuk.com> writes:
> On 26/10/2016 07:27, Ike Naar wrote:
>> On 2016-10-25, BartC <bc@freeuk.com> wrote:
>>> You don't need to explain why &*p is allowed
>>> but not & &**p or *&p!
>>
>> What makes you believe that *&p is not allowed?
>
> OK that one is allowed:
>
> *&*&*&*p;
>
> as is:
>
> &*&*&*p;
>
> when p is a pointer. But not:
>
> ***& & &p;
>
> or:
>
> & & &***p;  // allowed on some compilers when p is T***

Any compilers that do not diagnose that are non-conforming.
And the simple reason for that has been explained several times.

No doubt the inability to write & & &***p has been a great
inconvenience to you.

> If, however, you go through this on paper, striking through * followed 
> by &, or & followed by * with a pencil, and repeating, you end up with 
> just 'p' in all cases. And p doesn't need to be a pointer.
>
> On paper.

If I invent an arbitrary rule that doesn't actually exist in the
language, and then execute that rule using pencil and paper, I can
reach any nonsensical conclusion I like.  The & and * operators do
not arbitrarily cancel each other out, and your obsession with the
idea that they do or should is absurd.

-- 
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"