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  C++ Libraries
  
  ...one of the most highly
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 — Herb Sutter and Andrei
  Alexandrescu, C++
  Coding Standards
boost::pfr::greater — std::greater like comparator that returns boost::pfr::gt (x, y)
// In header: <boost/pfr/functors.hpp> template<typename T = void> struct greater { // public member functions bool operator()(const T &, const T &) const; };