Re: Document NULL

On 2025-Jun-18, David G. Johnston wrote:

> Version 8.
> 
> Marking this Ready to Commit in CF 2025-09 (CF PG19-1)

I have rebased this; here's v9.  I haven't reviewed it in depth, but
intend to give it a read and get it pushed sometime in the
not-too-distant future, so if anybody wants to review it some more, it'd
be appreciated.

Note that this rebase was across the func.sgml split, which means I had
to do some "manual" merging.  Looking at the git diff --stat output, it
seems to match what was there before, so I don't think anything was
lost.

-- 
Álvaro Herrera        Breisgau, Deutschland  —  https://www.EnterpriseDB.com/
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