ยง 10004. Effect of unconstitutionality in part. If any clause, sentence, paragraph, subdivision, section, rule or part of this chapter shall be adjudged by any court of competent jurisdiction to be invalid, such judgment shall not affect, impair or invalidate the remainder thereof, but shall be confined in its operation to the clause, sentence, paragraph, subdivision, section, rule or part thereof directly involved in the controversy in which such judgment shall have been rendered.