if (raw1 == null || raw2 == null)
{
throw new EvaluationException(LibFormulaErrorValue.ERROR_NA_VALUE);
}
final String text1 = typeRegistry.convertToText(value1.getType(), raw1);
final String text2 = typeRegistry.convertToText(value2.getType(), raw2);
if (text1 == null && text2 == null)
{
throw new EvaluationException
(LibFormulaErrorValue.ERROR_INVALID_ARGUMENT_VALUE);