Re: Backup Blacklist

[Juanma Barranquero]

On 1/2/07, Matthew Flaschen <matthew.flaschen@gatech.edu> wrote:

> Changing the default directory to the empty string fixed that.

Hmm, I don't think that's correct. Try with this (it has a couple
small bug fixes):


(require 'cl)
(require 'regexp-opt)

;; Set this to t or nil if you don't want the default.
;; It is used in my-backup-enable-predicate
(defvar my-backup-case-fold case-fold-search)

(defun my-exclude-from-backup (&rest files)
"Exclude from backup all filenames in FILES.
They must be absolute paths.
Other files are passed to `normal-backup-enable-predicate',
so is still possible for them to be excluded anyway."
(let ((excluded (get 'my-exclude-from-backup :files)))
  (mapc #'(lambda (file)
            (unless (file-name-absolute-p file)
              (error "%s is not an absolute filename" file))
            (pushnew (expand-file-name file) excluded :test #'equal))
        files)
  (put 'my-exclude-from-backup :files excluded)
  (put 'my-exclude-from-backup
       :regexp (concat "^" (regexp-opt excluded) "$"))))

(defun my-backup-enable-predicate (file)
"Alternate `backup-enable-predicate' function that excludes from
backups those files registered with `my-exclude-from-backup'."
(let ((regexp (get 'my-exclude-from-backup :regexp)))
  (if (and regexp
           (let ((case-fold-search my-backup-case-fold))
             (string-match regexp (expand-file-name file))))
      nil
    (normal-backup-enable-predicate file))))

(defun my-exclude-file-from-backup (&optional file)
(interactive (list (read-file-name "File to exclude: " nil nil t
                                   (file-name-nondirectory buffer-file-name))))
(my-exclude-from-backup file))

(setq backup-enable-predicate 'my-backup-enable-predicate)


> However, this also excludes other files containing the full path.  Thus,
>  for exampled, if I excluded:
>
> /data/Documents/cool.c
>
> It will also exclude
>
> /data/Documents/cool.cpp

Try now.

 (my-backup-enable-predicate "/data/Documents/cool.c")

should return nil, and

 (my-backup-enable-predicate "/data/Documents/cool.cpp")

should return t.

                   /L/e/k/t/u