David Rowley <david.rowley@2ndquadrant.com> writes:
> In Ottawa this year, Andres and I briefly talked about the possibility
> of making a series of changes to how equalfuncs.c works. The idea was
> to make it easy by using some pre-processor magic to allow us to
> create another version of equalfuncs which would let us have an equal
> comparison function that returns -1 / 0 / +1 rather than just true or
> false. This would allow us to Binary Search Trees of objects. I
> identified that EquivalenceClass.ec_members would be better written as
> a BST to allow much faster lookups in get_eclass_for_sort_expr().
This seems like a good idea, but why would we want to maintain two
versions? Just change equalfuncs.c into comparefuncs.c, full stop.
equal() would be a trivial wrapper for (compare_objects(a,b) == 0).
Andres' ideas about autogenerating all that boilerplate aren't
bad, but that's no justification for carrying two full sets of
per-node logic when one set would do.
regards, tom lane