Hello! Given a co-Buchi automaton and some number K, my function [1] creates another automaton ("co-Reachability") that bounds by K the maximal number of visits to co-Buchi accepting states. I currently create the new automaton like this: auto new_aut = make_twa_graph(aut->get_dict()) but this BDD-dictionary sharing between the new and the original automaton looks suspicious: once the original automaton dies and kills its dictionary (?), the new automaton will no longer be able to use it. Right? I guess the correct way is to create a new dictionary for the new automaton: auto new_d = spot::make_bdd_dict(); But then: what will be the natural way to copy edges of the original automaton into the new automaton? I currently simply iterate over edges of `aut` and do smth like: for (auto &t: aut->out(state)) k_aut->new_edge(src_state, dst_state, t.cond); where `t.cond` refers to a BDD of `aut`. So, I will need to create `cond` that uses new BDD dict, right? Which functions will be useful for doing that? Thanks! A minor point: If you use CUDD library and SPOT in the same project, then you will get compilation errors, because: CUDD does not use namespaces and has type `BDD`, and and Buddy in SPOT does not use namespaces and has `BDD`. To overcome the clash, the simple trick below works, but... maybe put Buddy into separate namespace? (minor feature request:) (I apologize for not providing the patch!) My current workaround is: whenever including SPOT headers, include them like this: #define BDD spotBDD #include <spot/twa/twagraph.hh> #include <spot/twaalgos/sccinfo.hh> #undef BDD best wishes, Ayrat Khalimov [1] https://github.com/5nizza/sdf-hoa/blob/master/src/k_reduce.cpp#L69