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



Defines comparison and stream operators for T along with hash_value function.


#include <boost/pfr/functions_for.hpp>
struct comparable_struct {      // No operators defined for that structure
    int i; short s; char data[7]; bool bl; int a,b,c,d,e,f;
// ...

comparable_struct s1 {0, 1, "Hello", false, 6,7,8,9,10,11};
comparable_struct s2 {0, 1, "Hello", false, 6,7,8,9,10,11111};
assert(s1 < s2);
std::cout << s1 << std::endl; // Outputs: {0, 1, H, e, l, l, o, , , 0, 6, 7, 8, 9, 10, 11}

See Also : 'Three ways of getting operators' for other ways to define operators and more details.

Defines following for T:

bool operator==(const T& lhs, const T& rhs);
bool operator!=(const T& lhs, const T& rhs);
bool operator< (const T& lhs, const T& rhs);
bool operator> (const T& lhs, const T& rhs);
bool operator<=(const T& lhs, const T& rhs);
bool operator>=(const T& lhs, const T& rhs);

template <class Char, class Traits>
std::basic_ostream<Char, Traits>& operator<<(std::basic_ostream<Char, Traits>& out, const T& value);

template <class Char, class Traits>
std::basic_istream<Char, Traits>& operator>>(std::basic_istream<Char, Traits>& in, T& value);

// helper function for Boost unordered containers and boost::hash<>.
std::size_t hash_value(const T& value);