RE: delete unneeded buffers

[Drew Adams]

>     does anyone know of a good way to kill unneeded buffers?
>     I think of something which kills all unvisible dired
>     buffers. Would be nice, if anyone has a suggestion.

Some possibilities:

* `C-x C-b', then mark the buffers you want to delete, then `x'.

* Use `ibuffer', then mark buffers by regexp or in other ways, then `x'. You can
mark by matching a regexp against buffer name, mode (e.g. Dired), or filename.

* In Icicles, `C-x k', then filter buffers (e.g. by regexp), then `C-!' (act on
all).

* Define your own Icicles multi-command that kills invisible Dired buffers -
they are the only possible completion candidates:

(icicle-define-command kill-invisible-dired-buffer
  "Kill invisible Dired buffer(s)."
  kill-buffer "Kill buffer: "
  (mapcar (lambda (b) (list (buffer-name b)))
          (buffer-list))
  (lambda (b)
    (let ((buf (get-buffer (car b))))
      (and (bufferp buf)
           (not (get-buffer-window buf 'visible))
           (with-current-buffer buf
             (eq major-mode 'dired-mode)))))
  t)

Or, better, to be sure *Completions* is updated properly after killing one or
more buffers, use this in the definition, in place of `kill-buffer': 

(lambda (b) (kill-buffer b) (icicle-complete-again-update))
  
With this command, completion candidates are the invisible Dired buffers. Your
minibuffer input at the prompt matches some of the buffers - it can be a regexp.
(Empty input matches all candidates.)

Use `C-!' to kill all buffers that match. Or click `C-mouse-2' in *Completions
to kill individual buffers (or cycle with the arrow keys and use `C-RET'). 

You can also select a bunch of candidates with the mouse and then act on them.
There are lots of possibilities -
http://www.emacswiki.org/cgi-bin/wiki/Icicles_-_Candidate_Sets.

The real point is that such a command is easy for *you* to define. You just
supply:

* the command name

* the action function: what `C-mouse-2' or `C-RET' does to a single candidate,
and what `C-!' does to each matching candidate

* the usual arguments to `completing-read':

  - prompt string
  - collection of possible candidates
  - predicate to filter those candidates
  - flag saying whether input must match (strict vs lax completion)