code: def state_check_collisions( state_engine, nameop, history_id_key, block_id, checked_ops, collision_checker ):
      
  
      # verify no collisions against already-accepted names
      collision_check = getattr( state_engine, collision_checker, None )
      try:
          assert collision_check is not None, "Collision-checker '%s' not defined" % collision_checker
          assert hasattr( collision_check, "__call__" ), "Collision-checker '%s' is not callable" % collision_checker
          assert history_id_key in nameop.keys(), "History ID key '%s' not in name operation" % (history_id_key)
          assert 'op' in nameop.keys(), "BUG: no op in nameop"
      except Exception, e:
          log.exception(e)
          log.error("FATAL: incorrect state_create() decorator")
          sys.exit(1)
  
      rc = collision_check( nameop[history_id_key], block_id, checked_ops )
      return rc
docs: See that there are no state-creating or state-preordering collisions at this block, for this history ID.
      Return True if collided; False if not