example: compile with mandatory c++17 mode, prepare std::string_view usage
example: compile with mandatory c++17 mode, prepare std::string_view usage

nu-book/zxing-cpp,huycn/zxing-cpp,huycn/zxing-cpp,nu-book/zxing-cpp,huycn/zxing-cpp,huycn/zxing-cpp,nu-book/zxing-cpp,nu-book/zxing-cpp,nu-book/zxing-cpp,nu-book/zxing-cpp,huycn/zxing-cpp,nu-book/zxing-cpp,nu-book/zxing-cpp,huycn/zxing-cpp,huycn/zxing-cpp,huycn/zxing-cpp