Re: Allow specifying NULL default in pg_proc.dat for "any" arguments

Andrew Dunstan <andrew(at)dunslane(dot)net> writes:
> On 2026-03-06 Fr 11:01 AM, Tom Lane wrote:
>> If we need a TypInfo[] entry for ANY, let's just add it.
>> But I haven't seen any use cases?

> Well, I guess that raises the question of what we get if we now do
> CREATE OR REPLACE FUNCTION foo(x int, VARIADIC y "any" DEFAULT NULL);
> which is the use case I was trying to avoid :-)
> Turns out it sets the type to "unknown" and the constlen to -2.

Hmm. Not sure if that matters or not. In any case, my objection
to the proposed patch was its side-effects on defaults that are of
regular data types. I don't think we want to change that behavior.

What exactly would be the use case for a default like the above?
I can see the point of, say, trying to merge the two variants of
jsonb_build_array:

CREATE FUNCTION pg_catalog.jsonb_build_array(VARIADIC "any") ...

CREATE FUNCTION pg_catalog.jsonb_build_array() ...

but introducing a default wouldn't help us do that, because it'd
still end up looking like a 1-argument call not a no-argument call.

regards, tom lane