Partly revert commit d9681fb94a3e04a618e58cd09df9cee929170edc about
when the arguments of a constructor can be moved at the place of the
variable on which destruct or induction applies.
Add printer for transparent state for ocamldebug.
One more word about "simpl f": avoid "simpl f" to be printed "simpl f",
at least when f is an evaluable reference.