string variables in LaTeX-indent-level-count: "" or nil?

[Mandar Mitra]

I just upgraded from MELPA last night. I'm looking at (no pun intended) the 
function LaTeX-indent-level-count in elpa/auctex-14.0.4/latex.el. It contains 
tests of the form

(looking-at LaTeX-indent-begin-regexp-exceptions-local)

(looking-at LaTeX-indent-begin-regexp-local)

(looking-at LaTeX-indent-end-regexp-local)

These variables seem to be nil by default, and looking-at is not happy, because 
it expects a string.

Is this oversight, or am I doing something wrong?