Apply font selection with buffer-face-mode-invoke

[Heime]

Have started making this function.  Currently it does a loop
and tries to apply the last font.  I want to allow for a user 
selection that will be used to call buffer-face-mode-invoke.

(defun mon-font-apply (font-family)


  (interactive
    (list
      (completing-read " Family: " (font-family-list) nil t)))

  (let ( (fonts (list-fonts (font-spec :family font-family))) )

    (if fonts

        (dolist (font fonts)

          (buffer-face-mode-invoke `(:font ,font) t))

      (message "No fonts found for family: %s" font-family))) )