regdatabase

Every once in a while, I find myself wanting to use regdatabase for
something like current_database()::regdatabase, and I'm always surprised
when I inevitably rediscover that it doesn't exist.  I only found one
reference to the idea in the archives [0].  So, I have two questions:

* Is there an easier way to get the current database's (or any database's)
  OID that I am overlooking (besides "SELECT oid FROM pg_database...")?

* Would anyone object if I put together some patches to add regdatabase?

[0] https://postgr.es/m/20191109220939.jz55zcc33d3g7h7b%40alap3.anarazel.de

-- 
nathan