c++ - Input from stream to enum type -

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how input stream enum type?

i can so

unsigned int sex = 0; stream >> sex; student.m_bio.sex = static_cast<sex>(sex);

otherwise?

inline std::istream & operator>>(std::istream & str, sex & v) {   unsigned int sex = 0;   if (str >> sex)     v = static_cast<sex>(sex);   return str; }

if want ensure value valid, can this:

enum sex {     male,     female,     sex_count };  inline std::istream & operator>>(std::istream & str, sex & v) {   unsigned int sex = 0;   if (!(str >> sex))     return str;   if (sex >= sex_count) {     str.setstate(str.rdstate() | std::ios::failbit);     return str;   }   v = static_cast<sex>(sex);   return str; }

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