std::isalnum, std::isspace, and std::isdigit all have assertions when built with the debug C++ runtime that get violated when a value is not in the property range (0 - 255) but since the type used in this library's is_alnum, etc, is char the range is actually -127 - 127 meaning that any bytes above 127 will cause a debug assertion failure.
std::isalnum,std::isspace, andstd::isdigitall have assertions when built with the debug C++ runtime that get violated when a value is not in the property range (0 - 255) but since the type used in this library'sis_alnum, etc, ischarthe range is actually -127 - 127 meaning that any bytes above 127 will cause a debug assertion failure.