Fix printing of monotypes. An earlier commit had resulted in monotypes being printed as "type () t" rather than "type t".
Fix printing of monotypes.
An earlier commit had resulted in monotypes being
printed as "type () t" rather than "type t".

dcjm/polyml,dcjm/polyml,polyml/polyml,dcjm/polyml,dcjm/polyml,polyml/polyml,polyml/polyml,polyml/polyml