Contains various informations about errors thrown by libxml.
the severity of the error (one of the following constants: LIBXML_ERR_WARNING, LIBXML_ERR_ERROR or LIBXML_ERR_FATAL)
The error's code.
The column where the error occurred.
Note: This property isn't entirely implemented in libxml and therefore 0 is often returned.
The error message, if any.
The filename, or empty if the XML was loaded from a string.
The line where the error occurred.