How catch the minibuffer message when saving, and colorize it? (Only for savings)

Question

You could colorize the message in the minibuffer with

    (message (propertize "foo bar" 'face '(:foreground "green" :weight bold)))

I would apply this only to the confirmation message of writings. The green color will help me to clearly distinct errors and confirmations from the minibuffer.

However, the confirmation message is different every time. So the confirmation message in the minibuffer could be like :

Wrote C:/foo.el

or

Wrote C:/bar.el

When searching around on Emacs Stackexchange, there are various ways to surpress or display another message. But they assume it's a static string message. It's not. The message differs each time, it's depends from the path/filename where the buffer will be stored.

Is there perhaps any way to recognize it's a write confirmation message, catch it, colorize it, and pass it further to the minibuffer?

Answer 1

You are referring to messages written to the echo area (not the minibuffer, though the screen space is the same -- the minibuffer is for input; the echo area is for output). And you are referring no doubt to such messages as the output of function message.

message is a built-in function (coded in C), and so in recent Emacs builds you cannot advise it. So you are out of luck wrt capturing its intended output and propertizing it.

But you can at least replace your own calls to message by calls to your own function, rene-message, which first propertizes the formatted string before then passing it to message. Something like this:

(defun rene-message (fmt-strg &rest strgs)
  (message "%s" (propertize (format fmt-strg strgs) 'face 'rene-emphasis))

But if you want to emphasize certain parts of the message then you are better off doing that directly where the message is created. For example:

(message "%s `%s' added to the `%s', file `%s'"
         type
         (propertize entry     'face 'rene-emphasis)
         (propertize set-name  'face 'rene-emphasis)
         (propertize file-name 'face 'rene-emphasis))