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Re: Add hint for function named "is" - Mailing list pgsql-hackers

From Greg Stark
Subject Re: Add hint for function named "is"
Date
Msg-id CAM-w4HOzC1vehF4XN5wEA_BiYYa_jMxDcN401RH6UTYq30eDzw@mail.gmail.com
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In response to Re: Add hint for function named "is"  (Tom Lane <tgl@sss.pgh.pa.us>)
Responses Re: Add hint for function named "is"  (Robert Haas <robertmhaas@gmail.com>)
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On Thu, Aug 11, 2016 at 10:54 PM, Tom Lane <tgl@sss.pgh.pa.us> wrote:

> I think what is happening
> in the trouble case is that since IS has lower precedence than Op, the
> grammar decides it ought to resolve || as a postfix operator, and then
> it effectively has
>         ('x' ||) IS ...
> which leaves noplace to go except IS NULL and other IS-something syntaxes.

I wonder whether it's really worth keeping postfix operators. They
seem to keep causing these kinds of headaches and I wonder how much
the grammar tables would be simplified by removing them.



-- 
greg

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