Unless the provision or context otherwise requires, these preliminary provisions and rules of construction shall govern the construction of this title.

Chapter, article, and section headings do not in any manner affect the scope, meaning, or intent of the provisions of this title.

Whenever any reference is made to any portion of this title or to any other statute, such reference shall apply to all amendments and additions heretofore or hereafter made.

Unless otherwise expressly stated:

occurs.

The present tense includes the past and future tenses; and the future, the present.

“Shall” is mandatory and “may” is permissive.

If any provision or clause of this title or application thereof to any person or circumstances is held invalid, the invalidity does not affect other provisions or applications of the title that can be given effect without the invalid provision or application, and to this end the provisions of this title are severable.