Re: [PATCHES] [GENERAL] Empty arrays with ARRAY[]

"Brendan Jurd" <direvus(at)gmail(dot)com> writes:
> As discussed on -hackers, this patch allows the construction of an
> empty array if an explicit cast to an array type is given (as in,
> ARRAY[]::int[]).

Applied with minor fixes; mostly, ensuring that the cast action would
propagate down to sub-arrays, as in

regression=# select array[[1],[2.2]]::int[];
array
-----------
{{1},{2}}
(1 row)

I was interested to realize that this fix validates the decision to
pass down the type information on-the-fly during transformExpr recursion.
It would have been a lot more painful to do it if we'd taken the A_Const
approach.

I didn't do anything about removing A_Const's typename field, but I'm
thinking that would be a good cleanup patch.

regards, tom lane