Re: proposal: new polymorphic types - commontype and commontypearray

I wrote:
> Here's a pretty-nearly-final version of the patch.
> In 0001 below, I've left it throwing an error for the case of all
> ANYCOMPATIBLE inputs being unknown, but the documentation fails to
> acknowledge that.  0002 below is a delta patch that switches to the
> other approach of resolving as TEXT.  I'm pretty well convinced that
> 0002 is what we should do, so I have not bothered to write a doc
> change that would explain 0001's behavior on this point.

Pushed with the resolve-to-TEXT mod, and some last-minute
polishing from a final re-read of the patch.

            regards, tom lane