Re: Convert macros to static inline functions

On Mon, May 16, 2022 at 1:28 AM Peter Eisentraut
<peter(dot)eisentraut(at)enterprisedb(dot)com> wrote:
> Inspired by [0], I looked to convert more macros to inline functions.
> The attached patches are organized "bottom up" in terms of their API
> layering; some of the later ones depend on some of the earlier ones.

Big +1 from me.

I converted over most of the nbtree.h function style macros in
Postgres 13, having put it off in Postgres 12 (there is one remaining
function macro due to an issue with #include dependencies). This
vastly improved the maintainability of the code, and I wish I'd done
it sooner.

Inline functions made it a lot easier to pepper various B-Tree code
utility functions with defensive assertions concerning preconditions
and postconditions. That's something that I am particular about. In
theory you can just use AssertMacro() in a function style macro. In
practice that approach is ugly, and necessitates thinking about
multiple evaluation hazards, which is enough to discourage good
defensive coding practices.

--
Peter Geoghegan