> The docs we have can be found at
> http://www.postgresql.org/devel-corner/docs/postgres/
> While they're usable, I don't think there's anyone around here who
> wouldn't agree that they could stand improvement. If you can read code
> and write English, then Uncle Sam wants *YOU* to help improve the docs.
> Feel free to step up to the plate and swing away ...
The docs for user-defined functions are very brief, but they do seem
to cover most of it, and they are mostly correct. It's not a fun
programming language, but I have written thousands of lines of it, and
it works. Maybe I'll try to document it a little bit.