Re: Array initialisation notation in syscache.c

On Wed, Dec 21, 2022 at 12:05 PM Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> wrote:
> Thomas Munro <thomas(dot)munro(at)gmail(dot)com> writes:
> > Do you think this is better?
>
> I'm not at all on board with adding runtime overhead to
> save maintaining the nkeys fields.

I don't see how to do it at compile time without getting the
preprocessor involved. What do you think about this version?

[ATTNUM] = {
AttributeRelationId,
AttributeRelidNumIndexId,
KEY(Anum_pg_attribute_attrelid,
Anum_pg_attribute_attnum),
128
},

> I'm kind of neutral on using "[N] = " as a substitute for
> ordering the entries correctly. While that does remove
> one failure mode, it seems like it adds another (ie
> failure to provide an entry at all would be masked).

It fails very early in testing if you do that. Admittedly, the
assertion is hard to understand, but if I add a new assertion close to
the cause with a new comment to say what you did wrong, I think that
should be good enough?