final Object startValue = parameters.getValue(1);
final Type lengthType = parameters.getType(2);
final Object lengthValue = parameters.getValue(2);
final String text = typeRegistry.convertToText(textType, textValue);
final Number start = typeRegistry.convertToNumber(startType, startValue);
final Number length = typeRegistry.convertToNumber(lengthType, lengthValue);
if(length.doubleValue() < 0 || start.doubleValue() < 1)
{
throw EvaluationException.getInstance(LibFormulaErrorValue.ERROR_INVALID_ARGUMENT_VALUE);