On Thu, Jan 6, 2011 at 12:32 PM, Jeff Davis <pg...@j-davis.com> wrote: > On Wed, 2011-01-05 at 12:07 -0800, Jeff Davis wrote: >> The current design for range types doesn't ask for add or subtract. >> Although it might be interesting to try to use such an interface for >> range types, it introduces a lot of complexity and makes it easier to >> cause subtle problems (consider that addition of timestamps and >> intervals is not commutative). > > A consequence of this design is that some generic range functions, like > "length" or "distance" would need to rely on the polymorphism of "+" and > "-" to work. > > I'm also not sure if a constructor like "range(start, offset) returns > anyrange" could be made to work generically at all, because the start > and offset may be two different types (and a function that takes > ANYELEMENT requires that all ANYELEMENT arguments are the same type). > > Does anyone see a problem with that?
Seems like you could make people who want that write range(start, start+offset) instead without too much pain. -- 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