Re: WIP: a way forward on bootstrap data

On 5/7/18, Mark Dilger <hornschnorter(at)gmail(dot)com> wrote:
> Hackers,
>
> Have you already considered and rejected the idea of having
> genbki.pl/Catalog.pm define constants that can be used in
> the catalog .dat files? I'm mostly curious if people think
> the resulting .dat files are better or worse using constants
> of this sort. For example:
...
> + # pg_cast constants for castcontext
> + use constant IMPLICIT => 'i';
> + use constant ASSIGNMENT => 'a';
> + use constant EXPLICIT => 'e';

The comment refers to pg_cast, but these constants apply globally.
It's also not the right place from a maintainability perspective, and
if it was, now these values have different macros defined in two
places. This is not good.

> - castcontext => 'a', castmethod => 'f' },
> + castcontext => ASSIGNMENT, castmethod => FUNCTION },

For one, this breaks convention that the values are always
single-quoted. If you had a use case for something like this, I would
instead use the existing lookup infrastructure and teach genbki.pl to
parse the enums (or #defines as the case might be) in the relevant
header file. You'd need some improvement in readability to justify
that additional code, though. I don't think this example quite passes
(it's pretty obvious locally what the letters refer to), but others
may feel differently.

-John Naylor