Hi, This is a follow up of "[string_ref] Add an equality operator between string_ref and char*" I'm sorry for the previous message, I'm started learning C++ and I'm making some errors Here the new topic: boost::string_ref rely on implicit conversation for using operators For example this operator: template bool operator==(basic_string_ref x, basic_string_ref y) Is bad because if I write this: boost::string_ref("http") == "http" The compiler complains: error: no match for ‘operator==’ (operand types are ‘boost::basic_string_ref’ and ‘const char [5]’) It can't find the correct overload because implicit conversion is considered after candidate templates have been considered boost::string_ref should offer overloads for string and const char* so it can be possible write code like boost::string_ref("boost") == "boost" && boost::string_ref("c++") == std::string("c++")