Re: Clear trailing whitespace on save, but not at the cursor

[Deniz Dogan <deniz@dogan.se>]

On 2012-03-05 12:02, Thien-Thi Nguyen wrote:
> () Aaron Meurer<asmeurer@gmail.com>
> () Sun, 4 Mar 2012 17:48:21 -0700
>
>     Is there a way to clear whitespace on save, but
>     then "put it back" where the cursor is?
>
> Here is one way:
>
> (defadvice delete-trailing-whitespace
>    (around except-for-current-line activate)
>    "However, leave trailing whitespace before point alone."
>    (let ((save (when (looking-back "\\s-+" (line-beginning-position) t)
>                  (match-string 0))))
>      ad-do-it
>      (when save (insert save))))
>

You could also use a function like the following:

(defun damd-delete-trailing-whitespace-except-current-line ()
   (interactive)
   (let ((back (1- (point-at-bol)))
         (front (1+ (point-at-eol))))
     (delete-trailing-whitespace (point-min) back)
     (delete-trailing-whitespace front (point-max))))

As you can see, I use the optional boundary arguments of 
`delete-trailing-whitespace' to achieve the affect.  It needs some 
tweaking, as in its current state it doesn't really check anything about 
the position of point in the current line.

Deniz