Method what

include/CoolProp/Exceptions.h:33–35

    CoolPropBaseError(const std::string& err, ErrCode code) throw() : m_code(code), m_err(err) {}
    ~CoolPropBaseError() throw() = default;
    const char* what() const throw() override {
        return m_err.c_str();
    }
    ErrCode code() {
        return m_code;
    }