Re: Precedence of standard comparison operators

On Wed, Mar 11, 2015 at 4:36 PM, Kevin Grittner <kgrittn(at)ymail(dot)com> wrote:
> If we ship with this off the results are entirely predictable. It
> will be somewhat surprising not to see any negative headlines about
> it.

Can you, or can anyone, show a plausible example of something that
would work under the old rules and work under the new rules but with a
different meaning? I have to admit that I'm having some difficulty
imagining exactly when that happens. Tom's examples upthread were not
things that seemed all that likely. The most plausible example was
probably a <= b || c, but the *old* interpretation of that is (a <= b)
|| c, so I'm having a little trouble taking that seriously as an
example of where this would cause a problem. If the old
interpretation had been a <= (b || c) and we were changing that to (a
<= b) || c, then, yeah, that could break things for a lot of people,
but not so many in this direction.

Are there better examples of how this is going to be bite people? I
really don't want to have another implicit-casting-changes type
debacle here.

--
Robert Haas
EnterpriseDB: http://www.enterprisedb.com
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