Empty system tables

While looking for tables related to default ops I came across the following
tables that are not mentioned in the programmer docs system catalogues
section and are (in my database anyway) empty. Perhaps someone who is
closer to the catalogues can confirm that these are still used. If so,
perhaps we can update the docs to describe them.

pg_inheritproc
pg_listener
pg_relcheck

The following tables are used but are not listed in the docs with the
rest. How about a short description of each? Maybe even add some to
the diagram.

pg_attrdef
pg_description
pg_inherits
pg_ipl
pg_rewrite
pg_shadow
pg_statistic
pg_trigger

I'm still trying to figure out why I get that fmgr error when I use my
user defined type in a where clause. Can anyone point me to the tables
that I need to modify? Here is what I have modified so far.

pg_opclass
pg_amop
pg_amproc
pg_description

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D'Arcy J.M. Cain <darcy(at){druid|vex}.net> | Democracy is three wolves
http://www.druid.net/darcy/ | and a sheep voting on
+1 416 424 2871 (DoD#0082) (eNTP) | what's for dinner.