root/branches/2.1/lisp/bookmark.el

;;; bookmark.el --- set bookmarks, maybe annotate them, jump to them later

;; Copyright (C) 1993, 1994, 1995, 1996, 1997, 2001 Free Software Foundation

;; Author: Karl Fogel <kfogel@red-bean.com>
;; Maintainer: Karl Fogel <kfogel@red-bean.com>
;; Created: July, 1993
;; Keywords: bookmarks, placeholders, annotations

;; This file is part of GNU Emacs.

;; GNU Emacs is free software; you can redistribute it and/or modify
;; it under the terms of the GNU General Public License as published by
;; the Free Software Foundation; either version 2, or (at your option)
;; any later version.

;; GNU Emacs is distributed in the hope that it will be useful,
;; but WITHOUT ANY WARRANTY; without even the implied warranty of
;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
;; GNU General Public License for more details.

;; You should have received a copy of the GNU General Public License
;; along with GNU Emacs; see the file COPYING.  If not, write to the
;; Free Software Foundation, Inc., 59 Temple Place - Suite 330,
;; Boston, MA 02111-1307, USA.

;;; Commentary:

;; This package is for setting "bookmarks" in files.  A bookmark
;; associates a string with a location in a certain file.  Thus, you
;; can navigate your way to that location by providing the string.
;; See the "User Variables" section for customizations.

;; Thanks to David Bremner <bremner@cs.sfu.ca> for thinking of and
;; then implementing the bookmark-current-bookmark idea.  He even
;; sent *patches*, bless his soul...

;; Thanks to Gregory M. Saunders <saunders@cis.ohio-state.edu> for
;; fixing and improving bookmark-time-to-save-p.

;; Thanks go to Andrew V. Klein <avk@cig.mot.com> for the code that
;; sorts the alist before presenting it to the user (in bookmark-bmenu-list
;; and the menu-bar).

;; And much thanks to David Hughes <djh@harston.cv.com> for many small
;; suggestions and the code to implement them (like
;; bookmark-bmenu-check-position, and some of the Lucid compatibility
;; stuff).

;; Kudos (whatever they are) go to Jim Blandy <jimb@red-bean.com>
;; for his eminently sensible suggestion to separate bookmark-jump
;; into bookmark-jump and bookmark-jump-noselect, which made many
;; other things cleaner as well.

;; Thanks to Roland McGrath for encouragement and help with defining
;; autoloads on the menu-bar.

;; Jonathan Stigelman <stig@hackvan.com> gave patches for default
;; values in bookmark-jump and bookmark-set.  Everybody please keep
;; all the keystrokes they save thereby and send them to him at the
;; end of each year :-)  (No, seriously, thanks Jonathan!)

;; Buckets of gratitude to John Grabowski <johng@media.mit.edu> for
;; thinking up the annotations feature and implementing it so well.

;; Based on info-bookmark.el, by Karl Fogel and Ken Olstad
;; <olstad@msc.edu>.

;; Thanks to Mikio Nakajima <PBC01764@niftyserve.or.jp> for many bugs
;; reported and fixed.

;; Thank you, Michael Kifer, for contributing the XEmacs support.

;; Enough with the credits already, get on to the good stuff:

;; FAVORITE CHINESE RESTAURANT:
;; Boy, that's a tough one.  Probably Hong Min, or maybe Emperor's
;; Choice (both in Chicago's Chinatown).  Well, both.  How about you?

;;; Code:

(require 'pp)

;;; Misc comments:
;;
;; If variable bookmark-use-annotations is non-nil, an annotation is
;; queried for when setting a bookmark.
;;
;; The bookmark list is sorted lexically by default, but you can turn
;; this off by setting bookmark-sort-flag to nil.  If it is nil, then
;; the list will be presented in the order it is recorded
;; (chronologically), which is actually fairly useful as well.

;;; User Variables

(defgroup bookmark nil
  "Setting, annotation and jumping to bookmarks."
  :group 'matching)


(defcustom bookmark-use-annotations nil
  "*If non-nil, saving a bookmark queries for an annotation in a buffer."
  :type 'boolean
  :group 'bookmark)


(defcustom bookmark-save-flag t
  "*Controls when Emacs saves bookmarks to a file.
--> nil means never save bookmarks, except when `bookmark-save' is
    explicitly called \(\\[bookmark-save]\).
--> t means save bookmarks when Emacs is killed.
--> Otherwise, it should be a number that is the frequency with which
    the bookmark list is saved \(i.e.: the number of times which
    Emacs' bookmark list may be modified before it is automatically
    saved.\).  If it is a number, Emacs will also automatically save
    bookmarks when it is killed.

Therefore, the way to get it to save every time you make or delete a
bookmark is to set this variable to 1 \(or 0, which produces the same
behavior.\)

To specify the file in which to save them, modify the variable
`bookmark-default-file', which is `~/.emacs.bmk' by default."
  :type '(choice (const nil) integer (other t))
  :group 'bookmark)


(defconst bookmark-old-default-file "~/.emacs-bkmrks"
  "*The `.emacs.bmk' file used to be called this name.")


;; defvarred to avoid a compilation warning:
(defvar bookmark-file nil
  "Old name for `bookmark-default-file'.")

(defcustom bookmark-default-file
  (if bookmark-file
      ;; In case user set `bookmark-file' in her .emacs:
      bookmark-file
    (convert-standard-filename "~/.emacs.bmk"))
  "*File in which to save bookmarks by default."
  :type 'file
  :group 'bookmark)


(defcustom bookmark-version-control 'nospecial
  "*Whether or not to make numbered backups of the bookmark file.
It can have four values: t, nil, `never', and `nospecial'.
The first three have the same meaning that they do for the
variable `version-control', and the final value `nospecial' means just
use the value of `version-control'."
  :type '(choice (const nil) (const never) (const nospecial)
                 (other t))
  :group 'bookmark)


(defcustom bookmark-completion-ignore-case t
  "*Non-nil means bookmark functions ignore case in completion."
  :type 'boolean
  :group 'bookmark)


(defcustom bookmark-sort-flag t
  "*Non-nil means that bookmarks will be displayed sorted by bookmark name.
Otherwise they will be displayed in LIFO order (that is, most
recently set ones come first, oldest ones come last)."
  :type 'boolean
  :group 'bookmark)


(defcustom bookmark-automatically-show-annotations t
  "*Nil means don't show annotations when jumping to a bookmark."
  :type 'boolean
  :group 'bookmark)


(defcustom bookmark-bmenu-file-column 30
  "*Column at which to display filenames in a buffer listing bookmarks.
You can toggle whether files are shown with \\<bookmark-bmenu-mode-map>\\[bookmark-bmenu-toggle-filenames]."
  :type 'integer
  :group 'bookmark)


(defcustom bookmark-bmenu-toggle-filenames t
  "*Non-nil means show filenames when listing bookmarks.
This may result in truncated bookmark names.  To disable this, put the
following in your `.emacs' file:

\(setq bookmark-bmenu-toggle-filenames nil\)"
  :type 'boolean
  :group 'bookmark)


(defcustom bookmark-menu-length 70
  "*Maximum length of a bookmark name displayed on a popup menu."
  :type 'integer
  :group 'boolean)


;;; No user-serviceable parts beyond this point.

;; Is it XEmacs?
(defconst bookmark-xemacsp
  (string-match "\\(Lucid\\|Xemacs\\)" emacs-version))


;; Added  for lucid emacs  compatibility, db
(or (fboundp 'defalias)  (fset 'defalias 'fset))

;; suggested for lucid compatibility by david hughes:
(or (fboundp 'frame-height)  (defalias 'frame-height 'screen-height))

;; This variable is probably obsolete now...
(or (boundp 'baud-rate)
    ;; some random value higher than 9600
    (setq baud-rate 19200))



;;; Keymap stuff:

;; Set up these bindings dumping time *only*;
;; if the user alters them, don't override the user when loading bookmark.el.

;;;###autoload (define-key ctl-x-map "rb" 'bookmark-jump)
;;;###autoload (define-key ctl-x-map "rm" 'bookmark-set)
;;;###autoload (define-key ctl-x-map "rl" 'bookmark-bmenu-list)

;;;###autoload
(defvar bookmark-map nil
  "Keymap containing bindings to bookmark functions.
It is not bound to any key by default: to bind it
so that you have a bookmark prefix, just use `global-set-key' and bind a
key of your choice to `bookmark-map'.  All interactive bookmark
functions have a binding in this keymap.")

;;;###autoload
(define-prefix-command 'bookmark-map)

;; Read the help on all of these functions for details...
;;;###autoload
(define-key bookmark-map "x" 'bookmark-set)
;;;###autoload
(define-key bookmark-map "m" 'bookmark-set) ; "m" for "mark"
;;;###autoload
(define-key bookmark-map "j" 'bookmark-jump)
;;;###autoload
(define-key bookmark-map "g" 'bookmark-jump) ; "g" for "go"
;;;###autoload
(define-key bookmark-map "i" 'bookmark-insert)
;;;###autoload
(define-key bookmark-map "e" 'edit-bookmarks)
;;;###autoload
(define-key bookmark-map "f" 'bookmark-insert-location) ; "f" for "find"
;;;###autoload
(define-key bookmark-map "r" 'bookmark-rename)
;;;###autoload
(define-key bookmark-map "d" 'bookmark-delete)
;;;###autoload
(define-key bookmark-map "l" 'bookmark-load)
;;;###autoload
(define-key bookmark-map "w" 'bookmark-write)
;;;###autoload
(define-key bookmark-map "s" 'bookmark-save)


;;; The annotation maps.
(defvar bookmark-read-annotation-mode-map (copy-keymap text-mode-map)
  "Keymap for composing an annotation for a bookmark.")

(define-key bookmark-read-annotation-mode-map "\C-c\C-c"
  'bookmark-send-annotation)



;;; Core variables and data structures:
(defvar bookmark-alist ()
  "Association list of bookmarks and their records.
You probably don't want to change the value of this alist yourself;
instead, let the various bookmark functions do it for you.

The format of the alist is

       \(BOOKMARK1 BOOKMARK2 ...\)

where each BOOKMARK is of the form

\(NAME
  \(filename . FILE\)
  \(front-context-string . FRONT-STR\)
  \(rear-context-string  . REAR-STR\)
  \(position . POS\)
  \(info-node . POS\)
  \(annotation . ANNOTATION\)\)

So the cdr of each bookmark is an alist too.
`info-node' is optional, by the way.")


(defvar bookmarks-already-loaded nil)


;; more stuff added by db.

(defvar bookmark-current-bookmark nil
  "Name of bookmark most recently used in the current file.
It is buffer local, used to make moving a bookmark forward
through a file easier.")

(make-variable-buffer-local 'bookmark-current-bookmark)


(defvar bookmark-alist-modification-count 0
  "Number of modifications to bookmark list since it was last saved.")


(defvar bookmark-search-size 16
  "Length of the context strings recorded on either side of a bookmark.")


(defvar bookmark-current-point 0)
(defvar bookmark-yank-point 0)
(defvar bookmark-current-buffer nil)



;; Helper functions.

;; Only functions on this page and the next one (file formats) need to
;; know anything about the format of bookmark-alist entries.
;; Everyone else should go through them.

(defun bookmark-name-from-full-record (full-record)
  "Return name of FULL-RECORD \(an alist element instead of a string\)."
  (car full-record))


(defun bookmark-all-names ()
  "Return a list of all current bookmark names."
  (bookmark-maybe-load-default-file)
  (mapcar
   (lambda (full-record)
     (bookmark-name-from-full-record full-record))
   bookmark-alist))


(defun bookmark-get-bookmark (bookmark)
  "Return the full entry for BOOKMARK in bookmark-alist.
If BOOKMARK is not a string, return nil."
  (when (stringp bookmark)
    (apply (if bookmark-completion-ignore-case
               #'assoc-ignore-case
             #'assoc)
           (list bookmark bookmark-alist))))


(defun bookmark-get-bookmark-record (bookmark)
  "Return the guts of the entry for BOOKMARK in bookmark-alist.
That is, all information but the name."
  (car (cdr (bookmark-get-bookmark bookmark))))


(defun bookmark-set-name (bookmark newname)
  "Set BOOKMARK's name to NEWNAME."
  (setcar
   (if (stringp bookmark) (bookmark-get-bookmark bookmark) bookmark)
   newname))


(defun bookmark-get-annotation (bookmark)
  "Return the annotation of BOOKMARK, or nil if none."
  (cdr (assq 'annotation (bookmark-get-bookmark-record bookmark))))


(defun bookmark-set-annotation (bookmark ann)
  "Set the annotation of BOOKMARK to ANN."
  (let ((cell (assq 'annotation (bookmark-get-bookmark-record bookmark))))
    (if cell
        (setcdr cell ann)
      (nconc (bookmark-get-bookmark-record bookmark)
             (list (cons 'annotation ann))))))


(defun bookmark-get-filename (bookmark)
  "Return the full filename of BOOKMARK."
  (cdr (assq 'filename (bookmark-get-bookmark-record bookmark))))


(defun bookmark-set-filename (bookmark filename)
  "Set the full filename of BOOKMARK to FILENAME."
  (let ((cell (assq 'filename (bookmark-get-bookmark-record bookmark))))
    (if cell
        (setcdr cell filename)
      (nconc (bookmark-get-bookmark-record bookmark)
             (list (cons 'filename filename))))))


(defun bookmark-get-position (bookmark)
  "Return the position \(i.e.: point\) of BOOKMARK."
  (cdr (assq 'position (bookmark-get-bookmark-record bookmark))))


(defun bookmark-set-position (bookmark position)
  "Set the position \(i.e.: point\) of BOOKMARK to POSITION."
  (let ((cell (assq 'position (bookmark-get-bookmark-record bookmark))))
    (if cell
        (setcdr cell position)
      (nconc (bookmark-get-bookmark-record bookmark)
             (list (cons 'position position))))))


(defun bookmark-get-front-context-string (bookmark)
  "Return the front-context-string of BOOKMARK."
  (cdr (assq 'front-context-string (bookmark-get-bookmark-record bookmark))))


(defun bookmark-set-front-context-string (bookmark string)
  "Set the front-context-string of BOOKMARK to STRING."
  (let ((cell (assq 'front-context-string
                    (bookmark-get-bookmark-record bookmark))))
    (if cell
        (setcdr cell string)
      (nconc (bookmark-get-bookmark-record bookmark)
             (list (cons 'front-context-string string))))))


(defun bookmark-get-rear-context-string (bookmark)
  "Return the rear-context-string of BOOKMARK."
  (cdr (assq 'rear-context-string (bookmark-get-bookmark-record bookmark))))


(defun bookmark-set-rear-context-string (bookmark string)
  "Set the rear-context-string of BOOKMARK to STRING."
  (let ((cell (assq 'rear-context-string
                    (bookmark-get-bookmark-record bookmark))))
    (if cell
        (setcdr cell string)
      (nconc (bookmark-get-bookmark-record bookmark)
             (list (cons 'rear-context-string string))))))


(defun bookmark-get-info-node (bookmark)
  "Get the info node associated with BOOKMARK."
  (cdr (assq 'info-node (bookmark-get-bookmark-record bookmark))))


(defun bookmark-set-info-node (bookmark node)
  "Set the Info node of BOOKMARK to NODE."
  (let ((cell (assq 'info-node
                    (bookmark-get-bookmark-record bookmark))))
    (if cell
        (setcdr cell node)
      (nconc (bookmark-get-bookmark-record bookmark)
             (list (cons 'info-node node)))))

  (message "%S" (assq 'info-node (bookmark-get-bookmark-record bookmark)))
  (sit-for 4)
  )


(defvar bookmark-history nil
  "The history list for bookmark functions.")


(defun bookmark-completing-read (prompt &optional default)
  "Prompting with PROMPT, read a bookmark name in completion.
PROMPT will get a \": \" stuck on the end no matter what, so you
probably don't want to include one yourself.
Optional second arg DEFAULT is a string to return if the user enters
the empty string."
  (bookmark-maybe-load-default-file) ; paranoia
  (let* ((completion-ignore-case bookmark-completion-ignore-case)
         (default default)
         (prompt (if default
                     (concat prompt (format " (%s): " default))
                   (concat prompt ": ")))
         (str
          (completing-read prompt
                           bookmark-alist
                           nil
                           0
                           nil
                           'bookmark-history)))
    (if (string-equal "" str)
        (list default)
      (list str))))


(defmacro bookmark-maybe-historicize-string (string)
  "Put STRING into the bookmark prompt history, if caller non-interactive.
We need this because sometimes bookmark functions are invoked from
menus, so `completing-read' never gets a chance to set `bookmark-history'."
  `(or
    (interactive-p)
    (setq bookmark-history (cons ,string bookmark-history))))


(defun bookmark-make (name &optional annotation overwrite info-node)
  "Make a bookmark named NAME.
Optional second arg ANNOTATION gives it an annotation.
Optional third arg OVERWRITE means replace any existing bookmarks with
this name.
Optional fourth arg INFO-NODE means this bookmark is at info node
INFO-NODE, so record this fact in the bookmark's entry."
  (bookmark-maybe-load-default-file)
  (let ((stripped-name (copy-sequence name)))
    (or bookmark-xemacsp
        ;; XEmacs's `set-text-properties' doesn't work on
        ;; free-standing strings, apparently.
        (set-text-properties 0 (length stripped-name) nil stripped-name))
    (if (and (bookmark-get-bookmark stripped-name) (not overwrite))
        ;; already existing bookmark under that name and
        ;; no prefix arg means just overwrite old bookmark
        (setcdr (bookmark-get-bookmark stripped-name)
                (list (bookmark-make-cell annotation info-node)))

      ;; otherwise just cons it onto the front (either the bookmark
      ;; doesn't exist already, or there is no prefix arg.  In either
      ;; case, we want the new bookmark consed onto the alist...)

      (setq bookmark-alist
            (cons
             (list stripped-name
                   (bookmark-make-cell annotation info-node))
             bookmark-alist)))

    ;; Added by db
    (setq bookmark-current-bookmark stripped-name)
    (setq bookmark-alist-modification-count
          (1+ bookmark-alist-modification-count))
    (if (bookmark-time-to-save-p)
        (bookmark-save))))


(defun bookmark-make-cell (annotation &optional info-node)
  "Return the record part of a new bookmark, given ANNOTATION.
Must be at the correct position in the buffer in which the bookmark is
being set.  This might change someday.
Optional second arg INFO-NODE means this bookmark is at info node
INFO-NODE, so record this fact in the bookmark's entry."
  (let ((the-record
         (` ((filename . (, (bookmark-buffer-file-name)))
             (front-context-string
              . (, (if (>= (- (point-max) (point)) bookmark-search-size)
                       (buffer-substring-no-properties
                        (point)
                        (+ (point) bookmark-search-size))
                     nil)))
             (rear-context-string
              . (, (if (>= (- (point) (point-min)) bookmark-search-size)
                       (buffer-substring-no-properties
                        (point)
                        (- (point) bookmark-search-size))
                     nil)))
             (position . (, (point)))
             ))))

    ;; Now fill in the optional parts:

    ;; Take no chances with text properties
    (set-text-properties 0 (length annotation) nil annotation)
    (set-text-properties 0 (length info-node) nil info-node)

    (if annotation
        (nconc the-record (list (cons 'annotation annotation))))
    (if info-node
        (nconc the-record (list (cons 'info-node info-node))))

    ;; Finally, return the completed record.
    the-record))



;;; File format stuff

;; The OLD format of the bookmark-alist was:
;;
;;       ((bookmark-name (filename
;;                        string-in-front
;;                        string-behind
;;                        point))
;;        ...)
;;
;; The NEW format of the bookmark-alist is:
;;
;;       ((bookmark-name ((filename . FILENAME)
;;                        (front-context-string . string-in-front)
;;                        (rear-context-string  . string-behind)
;;                        (position . POINT)
;;                        (annotation . annotation)
;;                        (whatever   . VALUE)
;;                        ...
;;                        ))
;;        ...)
;;
;;
;; I switched to using an internal as well as external alist because I
;; felt that would be a more flexible framework in which to add
;; features.  It means that the order in which values appear doesn't
;; matter, and it means that arbitrary values can be added without
;; risk of interfering with existing ones.
;;
;; BOOKMARK-NAME is the string the user gives the bookmark and
;; accesses it by from then on.
;;
;; FILENAME is the location of the file in which the bookmark is set.
;;
;; STRING-IN-FRONT is a string of `bookmark-search-size' chars of
;; context in front of the point at which the bookmark is set.
;;
;; STRING-BEHIND is the same thing, but after the point.
;;
;; The context strings exist so that modifications to a file don't
;; necessarily cause a bookmark's position to be invalidated.
;; bookmark-jump will search for STRING-BEHIND and STRING-IN-FRONT in
;; case the file has changed since the bookmark was set.  It will
;; attempt to place the user before the changes, if there were any.
;; ANNOTATION is the annotation for the bookmark; it may not exist
;; (for backward compatibility), be nil (no annotation), or be a
;; string.


(defconst bookmark-file-format-version 1
  "The current version of the format used by bookmark files.
You should never need to change this.")


(defconst bookmark-end-of-version-stamp-marker
  "-*- End Of Bookmark File Format Version Stamp -*-\n"
  "This string marks the end of the version stamp in a bookmark file.")


(defun bookmark-alist-from-buffer ()
  "Return a bookmark-alist (in any format) from the current buffer.
The buffer must of course contain bookmark format information.
Does not care from where in the buffer it is called, and does not
affect point."
  (save-excursion
    (goto-char (point-min))
    (if (search-forward bookmark-end-of-version-stamp-marker nil t)
        (read (current-buffer))
      ;; Else we're dealing with format version 0
      (if (search-forward "(" nil t)
          (progn
            (forward-char -1)
            (read (current-buffer)))
        ;; Else no hope of getting information here.
        (error "Not bookmark format")))))


(defun bookmark-upgrade-version-0-alist (old-list)
  "Upgrade a version 0 alist OLD-LIST to the current version."
  (mapcar
   (lambda (bookmark)
     (let* ((name      (car bookmark))
            (record    (car (cdr bookmark)))
            (filename  (nth 0 record))
            (front-str (nth 1 record))
            (rear-str  (nth 2 record))
            (position  (nth 3 record))
            (ann       (nth 4 record)))
       (list
        name
        (` ((filename             .    (, filename))
            (front-context-string .    (, (or front-str "")))
            (rear-context-string  .    (, (or rear-str  "")))
            (position             .    (, position))
            (annotation           .    (, ann)))))))
   old-list))


(defun bookmark-upgrade-file-format-from-0 ()
  "Upgrade a bookmark file of format 0 (the original format) to format 1.
This expects to be called from point-min in a bookmark file."
  (message "Upgrading bookmark format from 0 to %d..."
           bookmark-file-format-version)
  (let* ((old-list (bookmark-alist-from-buffer))
         (new-list (bookmark-upgrade-version-0-alist old-list)))
    (delete-region (point-min) (point-max))
    (bookmark-insert-file-format-version-stamp)
    (pp new-list (current-buffer))
    (save-buffer))
  (goto-char (point-min))
  (message "Upgrading bookmark format from 0 to %d...done"
           bookmark-file-format-version)
  )


(defun bookmark-grok-file-format-version ()
  "Return an integer which is the file-format version of this bookmark file.
This expects to be called from point-min in a bookmark file."
  (if (looking-at "^;;;;")
      (save-excursion
        (save-match-data
          (re-search-forward "[0-9]")
          (forward-char -1)
          (read (current-buffer))))
    ;; Else this is format version 0, the original one, which didn't
    ;; even have version stamps.
    0))


(defun bookmark-maybe-upgrade-file-format ()
  "Check the file-format version of this bookmark file.
If the version is not up-to-date, upgrade it automatically.
This expects to be called from point-min in a bookmark file."
  (let ((version (bookmark-grok-file-format-version)))
    (cond
     ((= version bookmark-file-format-version)
      ) ; home free -- version is current
     ((= version 0)
      (bookmark-upgrade-file-format-from-0))
     (t
      (error "Bookmark file format version strangeness")))))


(defun bookmark-insert-file-format-version-stamp ()
  "Insert text indicating current version of bookmark file format."
  (insert
   (format ";;;; Emacs Bookmark Format Version %d ;;;;\n"
           bookmark-file-format-version))
  (insert ";;; This format is meant to be slightly human-readable;\n"
          ";;; nevertheless, you probably don't want to edit it.\n"
          ";;; "
          bookmark-end-of-version-stamp-marker))


;;; end file-format stuff


;;; Core code:

;;;###autoload
(defun bookmark-set (&optional name parg)
  "Set a bookmark named NAME inside a file.
If name is nil, then the user will be prompted.
With prefix arg, will not overwrite a bookmark that has the same name
as NAME if such a bookmark already exists, but instead will \"push\"
the new bookmark onto the bookmark alist.  Thus the most recently set
bookmark with name NAME would be the one in effect at any given time,
but the others are still there, should you decide to delete the most
recent one.

To yank words from the text of the buffer and use them as part of the
bookmark name, type C-w while setting a bookmark.  Successive C-w's
yank successive words.

Typing C-u inserts the name of the last bookmark used in the buffer
\(as an aid in using a single bookmark name to track your progress
through a large file\).  If no bookmark was used, then C-u inserts the
name of the file being visited.

Use \\[bookmark-delete] to remove bookmarks \(you give it a name,
and it removes only the first instance of a bookmark with that name from
the list of bookmarks.\)"
  (interactive (list nil current-prefix-arg))
  (or
   (bookmark-buffer-file-name)
   (error "Buffer not visiting a file or directory"))

  (bookmark-maybe-load-default-file)

  (setq bookmark-current-point (point))
  (setq bookmark-yank-point (point))
  (setq bookmark-current-buffer (current-buffer))

  (let* ((default (or bookmark-current-bookmark
                      (bookmark-buffer-name)))
         (str
          (or name
              (read-from-minibuffer
               (format "Set bookmark (%s): " default)
               nil
               (let ((now-map (copy-keymap minibuffer-local-map)))
                 (define-key now-map "\C-w" 'bookmark-yank-word)
                 (define-key now-map "\C-u" 'bookmark-insert-current-bookmark)
                 now-map))))
         (annotation nil))
    (and (string-equal str "") (setq str default))
    ;; Ask for an annotation buffer for this bookmark
    (if bookmark-use-annotations
        (bookmark-read-annotation parg str)
      (bookmark-make str annotation parg (bookmark-info-current-node))
      (setq bookmark-current-bookmark str)
      (bookmark-bmenu-surreptitiously-rebuild-list)
      (goto-char bookmark-current-point))))


(defun bookmark-info-current-node ()
  "If in Info-mode, return current node name (a string), else nil."
  (if (eq major-mode 'Info-mode)
      Info-current-node))


(defun bookmark-kill-line (&optional newline-too)
  "Kill from point to end of line.
If optional arg NEWLINE-TOO is non-nil, delete the newline too.
Does not affect the kill-ring."
  (let ((eol (save-excursion (end-of-line) (point))))
    (delete-region (point) eol)
    (if (and newline-too (looking-at "\n"))
        (delete-char 1))))


;; Defvars to avoid compilation warnings:
(defvar bookmark-annotation-paragraph nil)
(defvar bookmark-annotation-name nil)
(defvar bookmark-annotation-buffer nil)
(defvar bookmark-annotation-file nil)
(defvar bookmark-annotation-point nil)


(defun bookmark-send-annotation ()
  "Use buffer contents as the annotation for a bookmark.
Exclude lines that begin with `#'.
Store the annotation text in the bookmark list with
the bookmark (and file, and point) specified in buffer local variables."
  (interactive)
  (if (not (eq major-mode 'bookmark-read-annotation-mode))
      (error "Not in bookmark-read-annotation-mode"))
  (goto-char (point-min))
  (while (< (point) (point-max))
    (if (looking-at "^#")
        (bookmark-kill-line t)
      (forward-line 1)))
  (let ((annotation (buffer-string))
        (parg bookmark-annotation-paragraph)
        (bookmark bookmark-annotation-name)
        (pt bookmark-annotation-point)
        (buf bookmark-annotation-buffer))
    ;; for bookmark-make-cell to work, we need to be
    ;; in the relevant buffer, at the relevant point.
    ;; Actually, bookmark-make-cell should probably be re-written,
    ;; to avoid this need.  Should I handle the error if a buffer is
    ;; killed between "C-x r m" and a "C-c C-c" in the annotation buffer?
    (save-excursion
      (pop-to-buffer buf)
      (goto-char pt)
      (bookmark-make bookmark annotation parg (bookmark-info-current-node))
      (setq bookmark-current-bookmark bookmark))
    (bookmark-bmenu-surreptitiously-rebuild-list)
    (goto-char bookmark-current-point))
  (kill-buffer (current-buffer)))


(defun bookmark-default-annotation-text (bookmark)
  (concat "#  Type the annotation for bookmark '" bookmark "' here.\n"
          "#  All lines which start with a '#' will be deleted.\n"
          "#  Type C-c C-c when done.\n#\n"
          "#  Author: " (user-full-name) " <" (user-login-name) "@"
          (system-name) ">\n"
          "#  Date:    " (current-time-string) "\n"))


(defvar bookmark-read-annotation-text-func 'bookmark-default-annotation-text
  "Function to return default text to use for a bookmark annotation.
It takes the name of the bookmark, as a string, as an arg.")

(defun bookmark-read-annotation-mode (buf point parg bookmark)
  "Mode for composing annotations for a bookmark.
Wants BUF POINT PARG and BOOKMARK.
When you have finished composing, type \\[bookmark-send-annotation] to send
the annotation.

\\{bookmark-read-annotation-mode-map}
"
  (interactive)
  (kill-all-local-variables)
  (make-local-variable 'bookmark-annotation-paragraph)
  (make-local-variable 'bookmark-annotation-name)
  (make-local-variable 'bookmark-annotation-buffer)
  (make-local-variable 'bookmark-annotation-file)
  (make-local-variable 'bookmark-annotation-point)
  (setq bookmark-annotation-paragraph parg)
  (setq bookmark-annotation-name bookmark)
  (setq bookmark-annotation-buffer buf)
  (setq bookmark-annotation-file (buffer-file-name buf))
  (setq bookmark-annotation-point point)
  (use-local-map bookmark-read-annotation-mode-map)
  (setq major-mode 'bookmark-read-annotation-mode)
  (insert (funcall bookmark-read-annotation-text-func bookmark))
  (run-hooks 'text-mode-hook))


(defun bookmark-read-annotation (parg bookmark)
  "Pop up a buffer for entering a bookmark annotation.
Text surrounding the bookmark is PARG; the bookmark name is BOOKMARK."
  (let ((buf (current-buffer))
        (point (point)))
    (pop-to-buffer (generate-new-buffer-name "*Bookmark Annotation Compose*"))
    (bookmark-read-annotation-mode buf point parg bookmark)))


(defvar bookmark-edit-annotation-mode-map (copy-keymap text-mode-map)
  "Keymap for editing an annotation of a bookmark.")


(define-key bookmark-edit-annotation-mode-map "\C-c\C-c"
  'bookmark-send-edited-annotation)