On Wed, Jun 1, 2016 at 10:27 AM, Tom Lane <t...@sss.pgh.pa.us> wrote: > As I understand it, the key problem is that tests like "is point on line" > would basically never succeed except in the most trivial cases, because of > roundoff error. That's not very nice, and it might cascade to larger > problems like object-containment tests failing unexpectedly. We would > need to go through all the geometric operations and figure out where that > kind of gotcha is significant and what we can do about it. Seems like a > fair amount of work :-(. If somebody's willing to do that kind of > investigation, then sure, but I don't think just blindly removing these > macros is going to lead to anything good.
Yeah, it does seem to need some research. > Also, I suppose this means that Robert promises not to make any of his > usual complaints about breaking compatibility? Because we certainly > would be. Pot, meet Mr. Kettle! Obviously, the inconvenience caused by any backward incompatibility has to be balanced against the fact that the new behavior is presumably better. But I stridently object to the accusation that of the two of us I'm the one more concerned with backward-compatibility. There may be some instances where I've had a more conservative judgement than you about breaking user-facing stuff, but you've blocked dozens of changes to the C API that would have enabled meaningful extension development on the grounds that somebody might complain when a future release changes the API! I think behavior changes that users will notice are of vastly greater significance than those which will only be observed by developers. In this particular case, I think that the current behavior is pretty stupid, and that the built-in geometric types are barely used, possibly because they have stupid behavior. So I would be willing to bet on a well-thought-out change in this area coming out to a net positive. -- Robert Haas EnterpriseDB: http://www.enterprisedb.com The Enterprise PostgreSQL Company -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
