Re: Cast has higher precedence than -

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От Tom Lane
Тема Re: Cast has higher precedence than -
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Msg-id 24974.1430700848@sss.pgh.pa.us
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Ответ на Cast has higher precedence than -  (Jim Nasby <Jim.Nasby@BlueTreble.com>)
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Jim Nasby <Jim.Nasby@BlueTreble.com> writes:
> The problem is that :: binds more tightly than -

This is well known, and even well documented.

> Is this by design? If not, any ideas how bad it'd be to fix?

It is by design.  The core argument for doing it is that '-' might have
type-dependent semantics that would not be reproduced by negating first
and casting afterwards.

Even if you could convince people that that concern is baseless, there
would be a backwards-compatibility problem.  For a comparison point,
note the hurdles I had to jump to persuade people that we should change
the precedence of comparison operators --- something that has clear
support in the standard, as this change would not.
        regards, tom lane



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