Re: Refactor construct_array() and deconstruct_array() for built-in types

Peter Eisentraut <peter(dot)eisentraut(at)enterprisedb(dot)com> writes:
> There are many calls to construct_array() and deconstruct_array() for
> built-in types, for example, when dealing with system catalog columns.
> These all hardcode the type attributes necessary to pass to these functions.

> To simplify this a bit, add construct_array_builtin(),
> deconstruct_array_builtin() as wrappers that centralize this hardcoded
> knowledge. This simplifies many call sites and reduces the amount of
> hardcoded stuff that is spread around.

> I also considered having genbki.pl generate lookup tables for these
> hardcoded values, similar to schemapg.h, but that ultimately seemed
> excessive.

+1 --- the added overhead of the switch statements is probably a
reasonable price to pay for the notational simplification and
bug-proofing.

One minor coding gripe is that compilers that don't know that elog(ERROR)
doesn't return will certainly generate "use of possibly-uninitialized
variable" complaints. Suggest inserting "return NULL;" or similar into
the default: cases. I'd also use more specific error wording to help
people find where they need to add code when they make use of a new type;
maybe like "type %u not supported by construct_array_builtin".

regards, tom lane