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? Regards, Jeff Davis -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers