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From: Kaz Kylheku <643-408-1753@kylheku.com>
Newsgroups: comp.lang.awk
Subject: Re: Operator precedence
Date: Sun, 26 May 2024 01:29:11 -0000 (UTC)
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On 2024-05-25, Janis Papanagnou <janis_papanagnou+ng@hotmail.com> wrote:
>> This creates a problem if we naively wedge exponentiation into
>> the grammar, by sticking it into a precedence level above
>> multiplication, but below unary.
>> 
>> The identity does not hold in exponentiation: (-A)**B
>> is not -(A**B).
>
> Looks like a non-sequitur to me.

Yes; the only point here is to explain why we don't notice this
issue, which is mirrored in multiplication: Given -A*B,
we can cheerfully stick a 0 on it to make 0-A*B. The value
does not surprisingly change. Yet, the underlying precedence
relationships are parallel to those in -A**B vs 0-A**B, where
there isn't an identity which masks the issue.

-- 
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