Re: Operator precedence

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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