Dean Rasheed <dean_rasheed(at)hotmail(dot)com> writes:
> My reason for asking is that some languages maintain a dependency tree
> of functions, and so could in theory do something clever with
> dependent functions - such as distinguishing between *declared* and
> *derived* volatility.
That might be possible in a system that only supports statically
analyzable functions, but Postgres is not such a system. Consider
EXECUTE in plpgsql, or anything at all in plperl or pltcl.
regards, tom lane