Re: Reducing header interdependencies around heapam.h et al.

On 2019-01-13 19:05:03 -0800, Andres Freund wrote:
> Hi,
> 
> On 2019-01-13 23:54:58 -0300, Alvaro Herrera wrote:
> > On 2019-Jan-13, Andres Freund wrote:
> > 
> > > Alvaro, you'd introduced the split of HeapScanDesc and HeapScanDescData
> > > being in different files (in a3540b0f657c6352) - what do you think about
> > > this change?  I didn't revert that split, but I think we ought to
> > > consider just relying on a forward declared struct in heapam.h instead,
> > > this split is pretty confusing and seems to lead to more interdependence
> > > in a lot of cases.
> > 
> > I wasn't terribly happy with that split, so I'm not opposed to doing
> > things differently.  For your consideration, I've had this patch lying
> > around for a few years, which (IIRC) reduces the exposure of heapam.h by
> > splitting relscan.h in two.  This applies on top of dd778e9d8884 (and as
> > I recall it worked well there).
> 
> You forgot to attach that patch... :).
> 
> I'm not sure I see a need to split relscan - note my patch makes it so
> that it's not included by heapam.h anymore, and doing for the same for
> genam.h would be fairly straightforward.  The most interesting bit there
> would be whether we'd add the includes necessary for Snapshot (imo no),
> Relation (?), ScanKey (imo no), or whether to add the necessary includes
> directly.

Here's a patch doing the same for genam as well.

Greetings,

Andres Freund