== step =====
step =>> t1.step   (*  :  *)
  t1.stepO =>> stepO   (*  :  *)
== upd =====
upd =>> t1.upd   (*  :  *)
  t1.updO =>> updO   (*  :  *)
== param =====
param =>> t1.param   (*  :  *)
== ctor =====
ctor =>> t1.ctor   (*  :  *)
== init =====
