Proper way of overloading binary relational operators in C++ -

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• what basic rules , idioms operator overloading? 7 answers

what proper/canonical way of overloading binary relational operators in c++?

is better use member functions, or friend free functions?

e.g.:

class x {  public:   ...    // use member function overloads   bool operator==(const x& rhs) const {      return m_text == rhs.m_text;    }   private:   std::string m_text; }; 

or:

class x {  public:   ...    // use friend free function overloads   friend bool operator==(const x& lhs, const x& rhs) {      return lhs.m_text == rhs.m_text;    }   private:   std::string m_text; }; 

the 1 thing should aware of implicit conversions.

if class supports implicit conversions other types, may useful make operator== friend support implicit conversions on first arguments.

in other cases suppose more matter of style.