- Item * o_l = dynamic_cast <Item *> (o);
- Item * n_l = n? dynamic_cast <Item *> (n) : 0;
- head_l_arr_.substitute ((Note_head*)o_l, (Note_head*)n_l);
- rest_l_arr_.substitute ((Rest*)o_l, (Rest*)n_l);
+ if (Note_head*h=dynamic_cast<Note_head*> (o))
+ head_l_arr_.substitute (h, dynamic_cast<Note_head*>(n));
+ if (Rest *r=dynamic_cast<Rest*> (o))
+ rest_l_arr_.substitute (r, dynamic_cast<Rest*>(n));