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Struct template less

boost::pfr::less — std::less like comparator that returns boost::pfr::lt (x, y)


// In header: <boost/pfr/functors.hpp>

template<typename T = void> 
struct less {
  // types
  typedef std::true_type is_transparent;  // This typedef exists only if T is void. 

  // public member functions
  bool operator()(const T &, const T &) const;
  template<typename V, typename U> bool operator()(const V &, const U &) const;


less public member functions

  1. bool operator()(const T & x, const T & y) const;


    true if field of x less than the field with same index of y and all previous fields of x equal to the same fields of y.

  2. template<typename V, typename U> 
      bool operator()(const V & x, const U & y) const;

    This operator allows comparison of x and y that have different type.


    Exists only if T is void.