xyh@nvn.xyz writes:
> Hello,
> In PostgreSQL 10.0 and 10.1 .
> psql \r is invalid.
Please say why you think this is "invalid". I'm pretty sure
it was an intentional behavioral change (associated with the
rewrite to support \if). In any case it's not obviously worse
than before. \r is supposed to clear the current query input
string; it says nothing about deleting history.
regards, tom lane
