root/trunk/lisp/textmodes/bibtex.el

;;; bibtex.el --- BibTeX mode for GNU Emacs

;; Copyright (C) 1992, 1994, 1995, 1996, 1997, 1998, 1999, 2001, 2002,
;;   2003, 2004, 2005, 2006, 2007, 2008 Free Software Foundation, Inc.

;; Author: Stefan Schoef <schoef@offis.uni-oldenburg.de>
;;      Bengt Martensson <bengt@mathematik.uni-Bremen.de>
;;      Marc Shapiro <marc.shapiro@acm.org>
;;      Mike Newton <newton@gumby.cs.caltech.edu>
;;      Aaron Larson <alarson@src.honeywell.com>
;;      Dirk Herrmann <D.Herrmann@tu-bs.de>
;; Maintainer: Roland Winkler <roland.winkler@physik.uni-erlangen.de>
;; Keywords: BibTeX, LaTeX, TeX

;; 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 3, 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., 51 Franklin Street, Fifth Floor,
;; Boston, MA 02110-1301, USA.

;;; Commentary:

;;  Major mode for editing and validating BibTeX files.

;;  Usage:
;;  See documentation for function bibtex-mode or type "\M-x describe-mode"
;;  when you are in BibTeX mode.

;;  Todo:
;;  Distribute texinfo file.

;;; Code:

(require 'button)


;; User Options:

(defgroup bibtex nil
  "BibTeX mode."
  :group 'tex
  :prefix "bibtex-")

(defgroup bibtex-autokey nil
  "Generate automatically a key from the author/editor and the title field."
  :group 'bibtex
  :prefix "bibtex-autokey-")

(defcustom bibtex-mode-hook nil
  "List of functions to call on entry to BibTeX mode."
  :group 'bibtex
  :type 'hook)

(defcustom bibtex-field-delimiters 'braces
  "Type of field delimiters.  Allowed values are `braces' or `double-quotes'."
  :group 'bibtex
  :type '(choice (const braces)
                 (const double-quotes)))

(defcustom bibtex-entry-delimiters 'braces
  "Type of entry delimiters.  Allowed values are `braces' or `parentheses'."
  :group 'bibtex
  :type '(choice (const braces)
                 (const parentheses)))

(defcustom bibtex-include-OPTcrossref '("InProceedings" "InCollection")
  "List of BibTeX entries that get an OPTcrossref field."
  :group 'bibtex
  :type '(repeat string))

(defcustom bibtex-include-OPTkey t
  "If non-nil, all newly created entries get an OPTkey field.
If this is a string, use it as the initial field text.
If this is a function, call it to generate the initial field text."
  :group 'bibtex
  :type '(choice (const :tag "None" nil)
                 (string :tag "Initial text")
                 (function :tag "Initialize Function")
                 (const :tag "Default" t)))
(put 'bibtex-include-OPTkey 'risky-local-variable t)

(defcustom bibtex-user-optional-fields
  '(("annote" "Personal annotation (ignored)"))
  "List of optional fields the user wants to have always present.
Entries should be of the same form as the OPTIONAL and
CROSSREF-OPTIONAL lists in `bibtex-entry-field-alist' (which see)."
  :group 'bibtex
  :type '(repeat (group (string :tag "Field")
                        (string :tag "Comment")
                        (option (choice :tag "Init"
                                        (const nil) string function)))))
(put 'bibtex-user-optional-fields 'risky-local-variable t)

(defcustom bibtex-entry-format
  '(opts-or-alts required-fields numerical-fields)
  "Type of formatting performed by `bibtex-clean-entry'.
It may be t, nil, or a list of symbols out of the following:
opts-or-alts        Delete empty optional and alternative fields and
                      remove OPT and ALT prefixes from used fields.
required-fields     Signal an error if a required field is missing.
numerical-fields    Delete delimiters around numeral fields.
page-dashes         Change double dashes in page field to single dash
                      (for scribe compatibility).
inherit-booktitle   If entry contains a crossref field and the booktitle
                      field is empty, set the booktitle field to the content
                      of the title field of the crossreferenced entry.
realign             Realign entries, so that field texts and perhaps equal
                      signs (depending on the value of
                      `bibtex-align-at-equal-sign') begin in the same column.
last-comma          Add or delete comma on end of last field in entry,
                      according to value of `bibtex-comma-after-last-field'.
delimiters          Change delimiters according to variables
                      `bibtex-field-delimiters' and `bibtex-entry-delimiters'.
unify-case          Change case of entry and field names.

The value t means do all of the above formatting actions.
The value nil means do no formatting at all."
  :group 'bibtex
  :type '(choice (const :tag "None" nil)
                 (const :tag "All" t)
                 (set :menu-tag "Some"
                      (const opts-or-alts)
                      (const required-fields)
                      (const numerical-fields)
                      (const page-dashes)
                      (const inherit-booktitle)
                      (const realign)
                      (const last-comma)
                      (const delimiters)
                      (const unify-case))))

(defcustom bibtex-clean-entry-hook nil
  "List of functions to call when entry has been cleaned.
Functions are called with point inside the cleaned entry, and the buffer
narrowed to just the entry."
  :group 'bibtex
  :type 'hook)

(defcustom bibtex-maintain-sorted-entries nil
  "If non-nil, BibTeX mode maintains all entries in sorted order.
Allowed non-nil values are:
plain or t   All entries are sorted alphabetically.
crossref     All entries are sorted alphabetically unless an entry has a
             crossref field.  These crossrefed entries are placed in
             alphabetical order immediately preceding the main entry.
entry-class  The entries are divided into classes according to their
             entry name, see `bibtex-sort-entry-class'.  Within each class
             the entries are sorted alphabetically.
See also `bibtex-sort-ignore-string-entries'."
  :group 'bibtex
  :type '(choice (const nil)
                 (const plain)
                 (const crossref)
                 (const entry-class)
                 (const t)))
(put 'bibtex-maintain-sorted-entries 'safe-local-variable
     '(lambda (a) (memq a '(nil t plain crossref entry-class))))

(defcustom bibtex-sort-entry-class
  '(("String")
    (catch-all)
    ("Book" "Proceedings"))
  "List of classes of BibTeX entry names, used for sorting entries.
If value of `bibtex-maintain-sorted-entries' is `entry-class'
entries are ordered according to the classes they belong to.  Each
class contains a list of entry names.  An entry `catch-all' applies
to all entries not explicitly mentioned."
  :group 'BibTeX
  :type '(repeat (choice :tag "Class"
                         (const :tag "catch-all" (catch-all))
                         (repeat :tag "Entry name" string))))
(put 'bibtex-sort-entry-class 'safe-local-variable
     (lambda (x) (let ((OK t))
              (while (consp x)
                (let ((y (pop x)))
                  (while (consp y)
                    (let ((z (pop y)))
                      (unless (or (stringp z) (eq z 'catch-all))
                        (setq OK nil))))
                  (unless (null y) (setq OK nil))))
              (unless (null x) (setq OK nil))
              OK)))

(defcustom bibtex-sort-ignore-string-entries t
  "If non-nil, BibTeX @String entries are not sort-significant.
That means they are ignored when determining ordering of the buffer
\(e.g., sorting, locating alphabetical position for new entries, etc.)."
  :group 'bibtex
  :type 'boolean)

(defcustom bibtex-field-kill-ring-max 20
  "Max length of `bibtex-field-kill-ring' before discarding oldest elements."
  :group 'bibtex
  :type 'integer)

(defcustom bibtex-entry-kill-ring-max 20
  "Max length of `bibtex-entry-kill-ring' before discarding oldest elements."
  :group 'bibtex
  :type 'integer)

(defcustom bibtex-parse-keys-timeout 60
  "Time interval in seconds for parsing BibTeX buffers during idle time.
Parsing initializes `bibtex-reference-keys' and `bibtex-strings'."
  :group 'bibtex
  :type 'integer)

(defcustom bibtex-parse-keys-fast t
  "If non-nil, use fast but simplified algorithm for parsing BibTeX keys.
If parsing fails, try to set this variable to nil."
  :group 'bibtex
  :type 'boolean)

(defcustom bibtex-entry-field-alist
  '(("Article"
     ((("author" "Author1 [and Author2 ...] [and others]")
       ("title" "Title of the article (BibTeX converts it to lowercase)")
       ("journal" "Name of the journal (use string, remove braces)")
       ("year" "Year of publication"))
      (("volume" "Volume of the journal")
       ("number" "Number of the journal (only allowed if entry contains volume)")
       ("pages" "Pages in the journal")
       ("month" "Month of the publication as a string (remove braces)")
       ("note" "Remarks to be put at the end of the \\bibitem")))
     ((("author" "Author1 [and Author2 ...] [and others]")
       ("title" "Title of the article (BibTeX converts it to lowercase)"))
      (("pages" "Pages in the journal")
       ("journal" "Name of the journal (use string, remove braces)")
       ("year" "Year of publication")
       ("volume" "Volume of the journal")
       ("number" "Number of the journal")
       ("month" "Month of the publication as a string (remove braces)")
       ("note" "Remarks to be put at the end of the \\bibitem"))))
    ("Book"
     ((("author" "Author1 [and Author2 ...] [and others]" nil t)
       ("editor" "Editor1 [and Editor2 ...] [and others]" nil t)
       ("title" "Title of the book")
       ("publisher" "Publishing company")
       ("year" "Year of publication"))
      (("volume" "Volume of the book in the series")
       ("number" "Number of the book in a small series (overwritten by volume)")
       ("series" "Series in which the book appeared")
       ("address" "Address of the publisher")
       ("edition" "Edition of the book as a capitalized English word")
       ("month" "Month of the publication as a string (remove braces)")
       ("note" "Remarks to be put at the end of the \\bibitem")))
     ((("author" "Author1 [and Author2 ...] [and others]" nil t)
       ("editor" "Editor1 [and Editor2 ...] [and others]" nil t)
       ("title" "Title of the book"))
      (("publisher" "Publishing company")
       ("year" "Year of publication")
       ("volume" "Volume of the book in the series")
       ("number" "Number of the book in a small series (overwritten by volume)")
       ("series" "Series in which the book appeared")
       ("address" "Address of the publisher")
       ("edition" "Edition of the book as a capitalized English word")
       ("month" "Month of the publication as a string (remove braces)")
       ("note" "Remarks to be put at the end of the \\bibitem"))))
    ("Booklet"
     ((("title" "Title of the booklet (BibTeX converts it to lowercase)"))
      (("author" "Author1 [and Author2 ...] [and others]")
       ("howpublished" "The way in which the booklet was published")
       ("address" "Address of the publisher")
       ("month" "Month of the publication as a string (remove braces)")
       ("year" "Year of publication")
       ("note" "Remarks to be put at the end of the \\bibitem"))))
    ("InBook"
     ((("author" "Author1 [and Author2 ...] [and others]" nil t)
       ("editor" "Editor1 [and Editor2 ...] [and others]" nil t)
       ("title" "Title of the book")
       ("chapter" "Chapter in the book")
       ("publisher" "Publishing company")
       ("year" "Year of publication"))
      (("volume" "Volume of the book in the series")
       ("number" "Number of the book in a small series (overwritten by volume)")
       ("series" "Series in which the book appeared")
       ("type" "Word to use instead of \"chapter\"")
       ("address" "Address of the publisher")
       ("edition" "Edition of the book as a capitalized English word")
       ("month" "Month of the publication as a string (remove braces)")
       ("pages" "Pages in the book")
       ("note" "Remarks to be put at the end of the \\bibitem")))
     ((("author" "Author1 [and Author2 ...] [and others]" nil t)
       ("editor" "Editor1 [and Editor2 ...] [and others]" nil t)
       ("title" "Title of the book")
       ("chapter" "Chapter in the book"))
      (("pages" "Pages in the book")
       ("publisher" "Publishing company")
       ("year" "Year of publication")
       ("volume" "Volume of the book in the series")
       ("number" "Number of the book in a small series (overwritten by volume)")
       ("series" "Series in which the book appeared")
       ("type" "Word to use instead of \"chapter\"")
       ("address" "Address of the publisher")
       ("edition" "Edition of the book as a capitalized English word")
       ("month" "Month of the publication as a string (remove braces)")
       ("note" "Remarks to be put at the end of the \\bibitem"))))
    ("InCollection"
     ((("author" "Author1 [and Author2 ...] [and others]")
       ("title" "Title of the article in book (BibTeX converts it to lowercase)")
       ("booktitle" "Name of the book")
       ("publisher" "Publishing company")
       ("year" "Year of publication"))
      (("editor" "Editor1 [and Editor2 ...] [and others]")
       ("volume" "Volume of the book in the series")
       ("number" "Number of the book in a small series (overwritten by volume)")
       ("series" "Series in which the book appeared")
       ("type" "Word to use instead of \"chapter\"")
       ("chapter" "Chapter in the book")
       ("pages" "Pages in the book")
       ("address" "Address of the publisher")
       ("edition" "Edition of the book as a capitalized English word")
       ("month" "Month of the publication as a string (remove braces)")
       ("note" "Remarks to be put at the end of the \\bibitem")))
     ((("author" "Author1 [and Author2 ...] [and others]")
       ("title" "Title of the article in book (BibTeX converts it to lowercase)")
       ("booktitle" "Name of the book"))
      (("pages" "Pages in the book")
       ("publisher" "Publishing company")
       ("year" "Year of publication")
       ("editor" "Editor1 [and Editor2 ...] [and others]")
       ("volume" "Volume of the book in the series")
       ("number" "Number of the book in a small series (overwritten by volume)")
       ("series" "Series in which the book appeared")
       ("type" "Word to use instead of \"chapter\"")
       ("chapter" "Chapter in the book")
       ("address" "Address of the publisher")
       ("edition" "Edition of the book as a capitalized English word")
       ("month" "Month of the publication as a string (remove braces)")
       ("note" "Remarks to be put at the end of the \\bibitem"))))
    ("InProceedings"
     ((("author" "Author1 [and Author2 ...] [and others]")
       ("title" "Title of the article in proceedings (BibTeX converts it to lowercase)")
       ("booktitle" "Name of the conference proceedings")
       ("year" "Year of publication"))
      (("editor" "Editor1 [and Editor2 ...] [and others]")
       ("volume" "Volume of the conference proceedings in the series")
       ("number" "Number of the conference proceedings in a small series (overwritten by volume)")
       ("series" "Series in which the conference proceedings appeared")
       ("pages" "Pages in the conference proceedings")
       ("address" "Location of the Proceedings")
       ("month" "Month of the publication as a string (remove braces)")
       ("organization" "Sponsoring organization of the conference")
       ("publisher" "Publishing company, its location")
       ("note" "Remarks to be put at the end of the \\bibitem")))
     ((("author" "Author1 [and Author2 ...] [and others]")
       ("title" "Title of the article in proceedings (BibTeX converts it to lowercase)"))
      (("booktitle" "Name of the conference proceedings")
       ("pages" "Pages in the conference proceedings")
       ("year" "Year of publication")
       ("editor" "Editor1 [and Editor2 ...] [and others]")
       ("volume" "Volume of the conference proceedings in the series")
       ("number" "Number of the conference proceedings in a small series (overwritten by volume)")
       ("series" "Series in which the conference proceedings appeared")
       ("address" "Location of the Proceedings")
       ("month" "Month of the publication as a string (remove braces)")
       ("organization" "Sponsoring organization of the conference")
       ("publisher" "Publishing company, its location")
       ("note" "Remarks to be put at the end of the \\bibitem"))))
    ("Manual"
     ((("title" "Title of the manual"))
      (("author" "Author1 [and Author2 ...] [and others]")
       ("organization" "Publishing organization of the manual")
       ("address" "Address of the organization")
       ("edition" "Edition of the manual as a capitalized English word")
       ("month" "Month of the publication as a string (remove braces)")
       ("year" "Year of publication")
       ("note" "Remarks to be put at the end of the \\bibitem"))))
    ("MastersThesis"
     ((("author" "Author1 [and Author2 ...] [and others]")
       ("title" "Title of the master\'s thesis (BibTeX converts it to lowercase)")
       ("school" "School where the master\'s thesis was written")
       ("year" "Year of publication"))
      (("type" "Type of the master\'s thesis (if other than \"Master\'s thesis\")")
       ("address" "Address of the school (if not part of field \"school\") or country")
       ("month" "Month of the publication as a string (remove braces)")
       ("note" "Remarks to be put at the end of the \\bibitem"))))
    ("Misc"
     (()
      (("author" "Author1 [and Author2 ...] [and others]")
       ("title" "Title of the work (BibTeX converts it to lowercase)")
       ("howpublished" "The way in which the work was published")
       ("month" "Month of the publication as a string (remove braces)")
       ("year" "Year of publication")
       ("note" "Remarks to be put at the end of the \\bibitem"))))
    ("PhdThesis"
     ((("author" "Author1 [and Author2 ...] [and others]")
       ("title" "Title of the PhD. thesis")
       ("school" "School where the PhD. thesis was written")
       ("year" "Year of publication"))
      (("type" "Type of the PhD. thesis")
       ("address" "Address of the school (if not part of field \"school\") or country")
       ("month" "Month of the publication as a string (remove braces)")
       ("note" "Remarks to be put at the end of the \\bibitem"))))
    ("Proceedings"
     ((("title" "Title of the conference proceedings")
       ("year" "Year of publication"))
      (("booktitle" "Title of the proceedings for cross references")
       ("editor" "Editor1 [and Editor2 ...] [and others]")
       ("volume" "Volume of the conference proceedings in the series")
       ("number" "Number of the conference proceedings in a small series (overwritten by volume)")
       ("series" "Series in which the conference proceedings appeared")
       ("address" "Location of the Proceedings")
       ("month" "Month of the publication as a string (remove braces)")
       ("organization" "Sponsoring organization of the conference")
       ("publisher" "Publishing company, its location")
       ("note" "Remarks to be put at the end of the \\bibitem"))))
    ("TechReport"
     ((("author" "Author1 [and Author2 ...] [and others]")
       ("title" "Title of the technical report (BibTeX converts it to lowercase)")
       ("institution" "Sponsoring institution of the report")
       ("year" "Year of publication"))
      (("type" "Type of the report (if other than \"technical report\")")
       ("number" "Number of the technical report")
       ("address" "Address of the institution (if not part of field \"institution\") or country")
       ("month" "Month of the publication as a string (remove braces)")
       ("note" "Remarks to be put at the end of the \\bibitem"))))
    ("Unpublished"
     ((("author" "Author1 [and Author2 ...] [and others]")
       ("title" "Title of the unpublished work (BibTeX converts it to lowercase)")
       ("note" "Remarks to be put at the end of the \\bibitem"))
      (("month" "Month of the publication as a string (remove braces)")
       ("year" "Year of publication")))))

  "List of BibTeX entry types and their associated fields.
List elements are triples
\(ENTRY-NAME (REQUIRED OPTIONAL) (CROSSREF-REQUIRED CROSSREF-OPTIONAL)).
ENTRY-NAME is the name of a BibTeX entry.  The remaining pairs contain
the required and optional fields of the BibTeX entry.
The second pair is used if a crossref field is present
and the first pair is used if a crossref field is absent.
If the second pair is nil, the first pair is always used.
REQUIRED, OPTIONAL, CROSSREF-REQUIRED and CROSSREF-OPTIONAL are lists.
Each element of these lists is a list of the form
\(FIELD-NAME COMMENT-STRING INIT ALTERNATIVE-FLAG).
COMMENT-STRING, INIT, and ALTERNATIVE-FLAG are optional.
FIELD-NAME is the name of the field, COMMENT-STRING is the comment that
appears in the echo area, INIT is either the initial content of the
field or a function, which is called to determine the initial content
of the field, and ALTERNATIVE-FLAG (either nil or t) marks if the
field is an alternative.  ALTERNATIVE-FLAG may be t only in the
REQUIRED or CROSSREF-REQUIRED lists."
  :group 'bibtex
  :type '(repeat (group (string :tag "Entry name")
                        (group (repeat :tag "Required fields"
                                       (group (string :tag "Field")
                                              (string :tag "Comment")
                                              (option (choice :tag "Init" :value nil
                                                              (const nil) string function))
                                              (option (choice :tag "Alternative"
                                                              (const :tag "No" nil)
                                                              (const :tag "Yes" t)))))
                               (repeat :tag "Optional fields"
                                       (group (string :tag "Field")
                                              (string :tag "Comment")
                                              (option (choice :tag "Init" :value nil
                                                              (const nil) string function)))))
                        (option :extra-offset -4
                         (group (repeat :tag "Crossref: required fields"
                                        (group (string :tag "Field")
                                               (string :tag "Comment")
                                               (option (choice :tag "Init" :value nil
                                                               (const nil) string function))
                                               (option (choice :tag "Alternative"
                                                               (const :tag "No" nil)
                                                               (const :tag "Yes" t)))))
                                (repeat :tag "Crossref: optional fields"
                                        (group (string :tag "Field")
                                               (string :tag "Comment")
                                               (option (choice :tag "Init" :value nil
                                                               (const nil) string function)))))))))
(put 'bibtex-entry-field-alist 'risky-local-variable t)

(defcustom bibtex-comment-start "@Comment"
  "String starting a BibTeX comment."
  :group 'bibtex
  :type 'string)

(defcustom bibtex-add-entry-hook nil
  "List of functions to call when BibTeX entry has been inserted."
  :group 'bibtex
  :type 'hook)

(defcustom bibtex-predefined-month-strings
  '(("jan" . "January")
    ("feb" . "February")
    ("mar" . "March")
    ("apr" . "April")
    ("may" . "May")
    ("jun" . "June")
    ("jul" . "July")
    ("aug" . "August")
    ("sep" . "September")
    ("oct" . "October")
    ("nov" . "November")
    ("dec" . "December"))
  "Alist of month string definitions used in the BibTeX style files.
Each element is a pair of strings (ABBREVIATION . EXPANSION)."
  :group 'bibtex
  :type '(repeat (cons (string :tag "Month abbreviation")
                       (string :tag "Month expansion"))))

(defcustom bibtex-predefined-strings
  (append
   bibtex-predefined-month-strings
   '(("acmcs"    . "ACM Computing Surveys")
     ("acta"     . "Acta Informatica")
     ("cacm"     . "Communications of the ACM")
     ("ibmjrd"   . "IBM Journal of Research and Development")
     ("ibmsj"    . "IBM Systems Journal")
     ("ieeese"   . "IEEE Transactions on Software Engineering")
     ("ieeetc"   . "IEEE Transactions on Computers")
     ("ieeetcad" . "IEEE Transactions on Computer-Aided Design of Integrated Circuits")
     ("ipl"      . "Information Processing Letters")
     ("jacm"     . "Journal of the ACM")
     ("jcss"     . "Journal of Computer and System Sciences")
     ("scp"      . "Science of Computer Programming")
     ("sicomp"   . "SIAM Journal on Computing")
     ("tcs"      . "Theoretical Computer Science")
     ("tocs"     . "ACM Transactions on Computer Systems")
     ("tods"     . "ACM Transactions on Database Systems")
     ("tog"      . "ACM Transactions on Graphics")
     ("toms"     . "ACM Transactions on Mathematical Software")
     ("toois"    . "ACM Transactions on Office Information Systems")
     ("toplas"   . "ACM Transactions on Programming Languages and Systems")))
  "Alist of string definitions used in the BibTeX style files.
Each element is a pair of strings (ABBREVIATION . EXPANSION)."
  :group 'bibtex
  :type '(repeat (cons (string :tag "String")
                       (string :tag "String expansion"))))

(defcustom bibtex-string-files nil
  "List of BibTeX files containing string definitions.
List elements can be absolute file names or file names relative
to the directories specified in `bibtex-string-file-path'."
  :group 'bibtex
  :type '(repeat file))

(defvar bibtex-string-file-path (getenv "BIBINPUTS")
  "*Colon separated list of paths to search for `bibtex-string-files'.")

(defcustom bibtex-files nil
  "List of BibTeX files that are searched for entry keys.
List elements can be absolute file names or file names relative to the
directories specified in `bibtex-file-path'.  If an element is a directory,
check all BibTeX files in this directory.  If an element is the symbol
`bibtex-file-path', check all BibTeX files in `bibtex-file-path'."
  :group 'bibtex
  :type '(repeat (choice (const :tag "bibtex-file-path" bibtex-file-path)
                         directory file)))

(defvar bibtex-file-path (getenv "BIBINPUTS")
  "*Colon separated list of paths to search for `bibtex-files'.")

(defcustom bibtex-help-message t
  "If non-nil print help messages in the echo area on entering a new field."
  :group 'bibtex
  :type 'boolean)

(defcustom bibtex-autokey-prefix-string ""
  "String prefix for automatically generated reference keys.
See `bibtex-generate-autokey' for details."
  :group 'bibtex-autokey
  :type 'string)

(defcustom bibtex-autokey-names 1
  "Number of names to use for the automatically generated reference key.
Possibly more names are used according to `bibtex-autokey-names-stretch'.
If this variable is nil, all names are used.
See `bibtex-generate-autokey' for details."
  :group 'bibtex-autokey
  :type '(choice (const :tag "All" infty)
                 integer))

(defcustom bibtex-autokey-names-stretch 0
  "Number of names that can additionally be used for reference keys.
These names are used only, if all names are used then.
See `bibtex-generate-autokey' for details."
  :group 'bibtex-autokey
  :type 'integer)

(defcustom bibtex-autokey-additional-names ""
  "String to append to the generated key if not all names could be used.
See `bibtex-generate-autokey' for details."
  :group 'bibtex-autokey
  :type 'string)

(defcustom bibtex-autokey-expand-strings nil
  "If non-nil, expand strings when extracting the content of a BibTeX field.
See `bibtex-generate-autokey' for details."
  :group 'bibtex-autokey
  :type 'boolean)

(defvar bibtex-autokey-transcriptions
  '(;; language specific characters
    ("\\\\aa" . "a")                      ; \aa           -> a
    ("\\\\AA" . "A")                      ; \AA           -> A
    ("\\\"a\\|\\\\\\\"a\\|\\\\ae" . "ae") ; "a,\"a,\ae    -> ae
    ("\\\"A\\|\\\\\\\"A\\|\\\\AE" . "Ae") ; "A,\"A,\AE    -> Ae
    ("\\\\i" . "i")                       ; \i            -> i
    ("\\\\j" . "j")                       ; \j            -> j
    ("\\\\l" . "l")                       ; \l            -> l
    ("\\\\L" . "L")                       ; \L            -> L
    ("\\\"o\\|\\\\\\\"o\\|\\\\o\\|\\\\oe" . "oe") ; "o,\"o,\o,\oe -> oe
    ("\\\"O\\|\\\\\\\"O\\|\\\\O\\|\\\\OE" . "Oe") ; "O,\"O,\O,\OE -> Oe
    ("\\\"s\\|\\\\\\\"s\\|\\\\3" . "ss")  ; "s,\"s,\3     -> ss
    ("\\\"u\\|\\\\\\\"u" . "ue")          ; "u,\"u        -> ue
    ("\\\"U\\|\\\\\\\"U" . "Ue")          ; "U,\"U        -> Ue
    ;; accents
    ("\\\\`\\|\\\\'\\|\\\\\\^\\|\\\\~\\|\\\\=\\|\\\\\\.\\|\\\\u\\|\\\\v\\|\\\\H\\|\\\\t\\|\\\\c\\|\\\\d\\|\\\\b" . "")
    ;; braces, quotes, concatenation.
    ("[`'\"{}#]" . "")
    ;; spaces
    ("\\\\?[ \t\n]+\\|~" . " "))
  "Alist of (OLD-REGEXP . NEW-STRING) pairs.
Used by the default values of `bibtex-autokey-name-change-strings' and
`bibtex-autokey-titleword-change-strings'.  Defaults to translating some
language specific characters to their ASCII transcriptions, and
removing any character accents.")

(defcustom bibtex-autokey-name-change-strings
  bibtex-autokey-transcriptions
  "Alist of (OLD-REGEXP . NEW-STRING) pairs.
Any part of a name matching OLD-REGEXP is replaced by NEW-STRING.
Case is significant in OLD-REGEXP.  All regexps are tried in the
order in which they appear in the list.
See `bibtex-generate-autokey' for details."
  :group 'bibtex-autokey
  :type '(repeat (cons (regexp :tag "Old")
                       (string :tag "New"))))