Peter Eisentraut <peter_e@gmx.net> writes:
> I find this all a bit premature, given that you haven't clearly defined what
> sort of user-visible functionality you hope to end up implementing.
That sums up my reaction too --- this looks like a solution in search of
a problem. The hook itself might be relatively harmless as long as it's
not in a performance-critical place, but I think people would tend to
contort their thinking to match what they can do with the hook rather
than think about what an ideal solution might be.
I'm also concerned that a hook like this is not usable unless there are
clear conventions about how multiple shared libraries should hook into
it simultaneously. The other hooks we have mostly aren't intended for
purposes that might need concurrent users of the hook, but it's hard
to argue that the case won't come up if this hook actually gets used.
regards, tom lane