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From: Keith Thompson <Keith.S.Thompson+u@gmail.com>
Newsgroups: comp.lang.c
Subject: Re: do { quit; } else { }
Date: Sun, 13 Apr 2025 14:58:11 -0700
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Kaz Kylheku <643-408-1753@kylheku.com> writes:
> On 2025-04-13, Michael S <already5chosen@yahoo.com> wrote:
>> The funny thing is that in original C prefix form of [] indexing was
>> equivalent to the postfix form.  May be, it still is in C23, I didn't
>> try to look in the docs or test.
>
> Are you thinking of a[i] being *(a + i) being i[a] due to commutativity?
>
> That's really not a useful feature. Actually right down to a + i being
> commutative when a is a pointer. It would be fine if only the
> <pointer> + <integer> combination were allowed.

Agreed.  The feature goes back to B, which was largely untyped, and
there wasn't a strong distinction between integers and pointers.  An
expression like 5[6] would refer to a memory location, and depending
on the system it might even work.

The transition from B to C was an opportunity to restrict the ordering
of the operands, but it wasn't taken.

-- 
Keith Thompson (The_Other_Keith) Keith.S.Thompson+u@gmail.com
void Void(void) { Void(); } /* The recursive call of the void */