>>108503945
>it's similar to manually doing it with a typecase on array-element-type
I didn't know about typecase and friends until you mentioned it. My desire for checking the type is for correctness rather than speed, so I decided to try to manually do it.
(defmethod load-resource ((src vector))
"Interpret `src' as a vector of plump-dom elements."
;; Manually type check contents of src to make sure
;; they're all of type plump-dom:node.
(loop for el across src
do (etypecase el
(plump-dom:node el)))
src)
