inline bool existIn(const FileProperty& input, const FPSet& container, FileProperty& output) { auto iter = container.find(input); if(iter == container.end()) return false; output = *iter; return true; }
inline bool insertInto(const FileProperty& fp, FPSet& container) { if(container.find(fp) == container.end()) { container.insert(fp); return true; } return false; }
inline bool existIn(const FileProperty& input, const FPSet& container) { if(container.find(input) == container.end()) return false; return true; }