Function swap

libraries/lib-note-track/NoteTrack.cpp:634–639

namespace
{
   void swap(std::unique_ptr<Alg_seq> &a, std::unique_ptr<Alg_seq> &b)
   {
      std::unique_ptr<Alg_seq> tmp = std::move(a);
      a = std::move(b);
      b = std::move(tmp);
   }
}

Alg_seq *NoteTrack::MakeExportableSeq(std::unique_ptr<Alg_seq> &cleanup) const