;;;
;; Set (default) dictionary
;;;
(setq ispell-dictionary "english")

;;;
;; Show default values for several variables, even if they are not defined before first call to 'ispell-word'
;;;
(when (boundp 'ispell-aspell-dictionary-alist)
  (progn
    (message "Default dictionary [%s]" ispell-dictionary)
    (message "Local dictionary [%s]" ispell-local-dictionary)
    (message "Current dictionary [%s]" ispell-current-dictionary)
    (prin1 "aspell-dictionary-alist:")
    (prin1 ispell-aspell-dictionary-alist)
  )
)

;;;
;; The call of 'ispell-word' runs several routines that populate several variables, especially '-dictionary-alist'.
;;;
(ispell-word "message")

;;;
;; Now output the same variables as above. They must have values.
;;;
(progn
  (message "Default dictionary [%s]" ispell-dictionary)
  (message "Local dictionary [%s]" ispell-local-dictionary)
  (message "Current dictionary [%s]" ispell-current-dictionary)
  (prin1 "aspell-dictionary-alist:")
  (prin1 ispell-aspell-dictionary-alist)
)

;;;
;; Second run of 'ispell-word'.
;;;
(ispell-word "message")

;;;
;; After second run variables might have other values.
;;;
(progn
  (message "Default dictionary [%s]" ispell-dictionary)
  (message "Local dictionary [%s]" ispell-local-dictionary)
  (message "Current dictionary [%s]" ispell-current-dictionary)
  (prin1 "aspell-dictionary-alist:")
  (prin1 ispell-aspell-dictionary-alist)
)