Fixing numerous `message' bugs..

[D. Goel <deego@gnufans.org>]

The emacs source code is littered with thousands of buggy calls to
`message'.  Here is an example of such a structure:


(message 
	(if foo
		nil
		(if bar "abc"
			(concat "def" filename))))

This example will lead to an error if the filename has %s in it. 

At the same time, the simplistic fix of replacing (message by (message
"%s" would be incorrect because if foo is true, the coder wanted
(message nil), and not (message "%s" nil).


The appropriate fix to this would be

(let ((arg ((rest-of-the-code))))
	(if (null arg)
	(message nil)
	(message "%s" arg)))

^^^ This fix will have to be repeated thousands of time as I go
through the source code.

It would rather make much more sense to code this fix into a little
function:

(defun msg (arg)
	(if (null arg)
	(message nil)
	(message (format "%s" arg))))


Then, I simply have to replace buggy calls to `message' with `msg'

----

.. this new function can be further improved to be more general, so
that develepors can simply start preferring the new msg if they like -

(defun msg (&rest args)
     (cond
      ((null args) (message nil))
      ((null (car args) (message nil)))
      ((= (length args) 1) (message "%s" (car args)))
      (apply 'message args)))


I would like to add `msg' to simple.el, and replace buggy `message'
calls by `msg'.  Can you please confirm or comment?


((My correct email is now deego3@gmail.com, please cc there as well;
emacs-devel seems to send those messages to spam, so I am emailing
from my older gnufans address.  If an admin sees this, can you please
unblock my other email to emacs-devel sent earlier today about a
bugfix I made to find-func.el? thanks.)

- deego (Deepak Goel)