transliterate.el

(defvar transliterate-custom
  '((?— . " , ")
    (?– . " through "))
  "Custom transliterations when the Unicode table isn't useful.")

(defun transliterate-char (c)
  "Return ASCII string for C, or nil for combining characters."
  (if (<= c 127)
      (char-to-string c)
    (let ((name (downcase (or (get-char-code-property c 'old-name)
                              (get-char-code-property c 'name))))
          (category (get-char-code-property c 'general-category))
          (custom (cdr (assoc c transliterate-custom))))
      (cond (custom custom)
            ((member category '(Mn Mc Me)) nil)
            ((replace-regexp-in-string " sign$" "" name))))))

(defun transliterate-buffer ()
  "Run `transliterate-char' over entire buffer."
  (interactive)
  (save-excursion
    (setf (point) (point-min))
    (while (< (point) (point-max))
      (let* ((char (char-after))
             (translation (transliterate-char char)))
        (delete-char 1)
        (when translation
          (insert translation))))))