petere@postgresql.org (Peter Eisentraut) writes:
> Log Message:
> -----------
> Add support for xmlval IS DOCUMENT expression.
I don't think I trust your reverse-listing of IS DOCUMENT; you need
parens around the argument to be sure it is parsed the same way next
time, if it's not a trivial expression.
Or you could teach the pretty-print code the correct precedence rules,
but this patch hasn't done that.
regards, tom lane