TIL that `defvar` in #emacs-lisp won't update a variable's value if it's already been set. No wonder I've been getting dates from last week, when I've been trying to get today's.
"The defvar special form is similar to setq in that it sets the value of a variable. It is unlike setq in two ways: first, it only sets the value of the variable if the variable does not already have a value. If the variable already has a value, defvar does not override the existing value. Second, defvar has a documentation string."
https://www.gnu.org/software/emacs/manual/html_node/eintr/defvar.html
Documentation string on a variable is pretty rad, though.
Noted this, as well as some other things I learned when writing emacs-lisp: https://newschematic.org/blog/writing-an-elisp-function/
