Re: ElDoc: adding optional support to display messages in header-line instead of the echo area

[Geralt <usr.gentoo@googlemail.com>]

On Tue, Aug 4, 2009 at 10:32 AM, martin rudalics<rudalics@gmx.at> wrote:
>> can you explain why? I put the omessage into the ELSE block because
>> somebody on emacs-help suggested it and it made sense to me at that
>> time.
>
> Compiling eldoc.el after applying your patch gets me
>
> eldoc-new.el~:550:1:Warning: the function `omessage' is not known to be
>    defined.
>
> This happens because in the
>
>      (cond (eldoc-last-message (if eldoc-display-in-header-line
>                                    (setq header-line-format
> eldoc-last-message)
>                                  (message "%s" eldoc-last-message)
>                                  (omessage (message nil)))))))
>
> form you misplaced the parentheses and thus `omessage' is not considered
> a condition of some clause of the `cond' special form but as a function
> call.
>
> BTW, I suppose you also need to call `force-mode-line-update' because
> Emacs does not necessarily update the contents of the header line when
> just moving point.
>
> martin
>

Ok, I did all the changes, here's the patch with all the changes:

--- eldoc.el	2009-08-04 20:48:20.789335848 +0200
+++ eldoc.el	2009-08-04 20:47:34.350337476 +0200
@@ -105,6 +105,11 @@
  enable argument list to fit on one line" truncate-sym-name-if-fit))
   :group 'eldoc)

+(defcustom eldoc-display-in-header-line nil
+  "If set eldoc will display its messages in the topmost line of the
window, called the header-line, instead of the echo area."
+  :type 'boolean
+  :group 'eldoc)
+
 (defface eldoc-highlight-function-argument
   '((t (:inherit bold)))
   "Face used for the argument at point in a function's argument list.
@@ -201,7 +206,11 @@
     ;; they are Legion.
     ;; Emacs way of preventing log messages.
     (let ((message-log-max nil))
-      (cond (eldoc-last-message (message "%s" eldoc-last-message))
+      (cond (eldoc-last-message (if eldoc-display-in-header-line
+				    (progn
+				      (setq header-line-format eldoc-last-message)
+				      (force-mode-line-update))
+				  (message "%s" eldoc-last-message)))
 	    (omessage (message nil)))))
   eldoc-last-message)



Geralt.