This one bit me yesterday on Emacs 29.3 as I was revising my init file (for
the thousandth time this week).

As setopt becomes more widely recommended, people will likely encounter
situations like the below where they expect constant numeric types to be
coerced.

(defcustom temp-float "Float"
  "Float type."
  :type 'float)

(setopt temp-float 2.0) ; works
(setopt temp-float 2) ; Warning (emacs): Value '2' does not match type float

-Stephane

P.S. I reported a bug to Prot as some much more complex modus defcustom
type definitions seem either themselves broken or setopt needs some work to
accommodate them.