now hunspell can check camel case word

README.org

@@ -97,6 +97,21 @@ But my =w3m= based utilities can open video/audio/image with the help of =w3m=.
 - I recommend aspell for programmers. Non-programmers find hunspell is better on typo correction
 
 If you use hunspell, check [[http://blog.binchen.org/posts/what-s-the-best-spell-check-set-up-in-emacs.html][my article]]. Please note the hunspell executable understands either unix format path or windows format path but not both. You need figure out hunspell version you are using.
+
+You can set =force-to-use-hunspell= in =init-spelling.el= if you prefer hunspell.
+
+This seutp can spell check  camel case words either using aspell or hunspell.
+
+Aspell's default personal English dictionary is =$HOME/.aspell.en.pws=. It's content is like:
+#+begin_src conf
+personal_ws-1.1 en 4
+ABN
+ACC
+ACN
+ACT
+#+end_src
+
+Hunspell's default personal English dictionary is =$HOME/.hunspell_en_US=. The file format is same as aspell.
 **** sbcl (lisp environment)
 - Required by lisp =slime=
 - Install through OS package manager

lisp/init-spelling.el

@@ -39,15 +39,30 @@
   "A callback to check WORD.  Return t if WORD is typo.")
 
 (defun my-flyspell-predicate (word)
-  "Use aspell to check WORD.  If it's typo return true."
-  (if (string-match-p "^&"
-                      (shell-command-to-string (format "echo %s | %s %s pipe"
-                                                       word
-                                                       ispell-program-name
-                                                       (mapconcat 'identity
-                                                                  (flyspell-detect-ispell-args t)
-                                                                  " "))))
-      t))
+  "Use aspell to check WORD.  If it's typo return t."
+  (let* ((cmd (cond
+               ;; aspell: `echo "helle world" | aspell pipe`
+               ((string-match-p "aspell$" ispell-program-name)
+                (format "echo \"%s\" | %s pipe"
+                        word
+                        ispell-program-name))
+               ;; hunspell: `echo "helle world" | hunspell -a -d en_US`
+               (t
+                (format "echo \"%s\" | %s -a -d en_US"
+                        word
+                        ispell-program-name))))
+         (cmd-output (shell-command-to-string cmd))
+         rlt)
+    ;; (message "word=%s cmd=%s" word cmd)
+    ;; (message "cmd-output=%s" cmd-output)
+    (cond
+     ((string-match-p "^&" cmd-output)
+      ;; it's a typo because at least one sub-word is typo
+      (setq rlt t))
+     (t
+      ;; not a typo
+      (setq rlt nil)))
+    rlt))
 
 (defun js-flyspell-verify ()
   (let* ((case-fold-search nil)
@@ -69,12 +84,15 @@
     (cond
      ((not font-matched)
       (setq rlt nil))
-     ((not (string-match-p "aspell$" ispell-program-name))
-      ;; Only override aspell's result
-      (setq rlt t))
+
+     ;; ((not (string-match-p "aspell$" ispell-program-name))
+     ;;  ;; Only override aspell's result
+     ;;  (setq rlt t))
+
      ;; ignore two character word
      ((< (length (setq word (thing-at-point 'word))) 2)
       (setq rlt nil))
+
      ;; handle camel case word
      ((and (setq subwords (split-camel-case word)) (> (length subwords) 1))
       (let* ((s (mapconcat (lambda (w)
@@ -86,6 +104,8 @@
                               (t
                                w))) subwords " ")))
         (setq rlt (my-flyspell-predicate s))))
+
+     ;; `extra-flyspell-predicate' actually do nothing by default
      (t
       (setq rlt (funcall extra-flyspell-predicate word))))
     rlt))
@@ -145,9 +165,16 @@ Please note RUN-TOGETHER will make aspell less capable. So it should only be use
 ;; hunspell will search for a dictionary called `en_US' in the path specified by
 ;; `$DICPATH'
 
+(defvar force-to-use-hunspell nil
+  "If t, force to use hunspell.  Or else, search aspell at first and fall
+back to hunspell if aspell is not found.")
+
 (cond
- ((executable-find "aspell")
+ ;; use aspell
+ ((and (not force-to-use-hunspell) (executable-find "aspell"))
   (setq ispell-program-name "aspell"))
+
+ ;; use hunspell
  ((executable-find "hunspell")
   (setq ispell-program-name "hunspell")
   (setq ispell-local-dictionary "en_US")