-._protesilaos-s-___denote___.-/README.org

#+title: denote: Simple notes with a strict file-naming scheme
#+author: Protesilaos Stavrou
#+email: info@protesilaos.com
#+language: en
#+options: ':t toc:nil author:t email:t num:t
#+startup: content

#+macro: stable-version N/A
#+macro: release-date N/A
#+macro: development-version 0.1.0-dev
#+macro: file @@texinfo:@file{@@$1@@texinfo:}@@
#+macro: space @@texinfo:@: @@
#+macro: kbd @@texinfo:@kbd{@@$1@@texinfo:}@@

#+export_file_name: denote.texi

#+texinfo_filename: denote.info
#+texinfo_dir_category: Emacs misc features
#+texinfo_dir_title: Denote: (denote)
#+texinfo_dir_desc: Simple notes with a strict file-naming scheme
#+texinfo_header: @set MAINTAINERSITE @uref{https://protesilaos.com,maintainer webpage}
#+texinfo_header: @set MAINTAINER Protesilaos Stavrou
#+texinfo_header: @set MAINTAINEREMAIL @email{info@protesilaos.com}
#+texinfo_header: @set MAINTAINERCONTACT @uref{mailto:info@protesilaos.com,contact the maintainer}

#+texinfo: @insertcopying

This manual, written by Protesilaos Stavrou, describes the customization
options for the Emacs package called =denote= (or =denote.el=), and
provides every other piece of information pertinent to it.

The documentation furnished herein corresponds to stable version
{{{stable-version}}}, released on {{{release-date}}}.  Any reference to
a newer feature which does not yet form part of the latest tagged
commit, is explicitly marked as such.

Current development target is {{{development-version}}}.  Note that the
project is still in active development and THINGS MIGHT CHANGE IN
BACKWARD-INCOMPATIBLE WAYS until we make the first stable release.

+ Homepage: https://protesilaos.com/emacs/denote.
# + Change log: https://protesilaos.com/emacs/denote-changelog.
+ Git repository: https://git.sr.ht/~protesilaos/denote.
+ Mailing list: https://lists.sr.ht/~protesilaos/denote.

#+toc: headlines 8 insert TOC here, with eight headline levels

* COPYING
:PROPERTIES:
:COPYING: t
:CUSTOM_ID: h:40b18bb2-4dc1-4202-bd0b-6fab535b2a0f
:END:

Copyright (C) 2022  Free Software Foundation, Inc.

#+begin_quote
Permission is granted to copy, distribute and/or modify this document
under the terms of the GNU Free Documentation License, Version 1.3 or
any later version published by the Free Software Foundation; with no
Invariant Sections, with the Front-Cover Texts being “A GNU Manual,” and
with the Back-Cover Texts as in (a) below.  A copy of the license is
included in the section entitled “GNU Free Documentation License.”

(a) The FSF’s Back-Cover Text is: “You have the freedom to copy and
modify this GNU manual.”
#+end_quote

* Overview
:PROPERTIES:
:CUSTOM_ID: h:a09b70a2-ae0b-4855-ac14-1dddfc8e3241
:END:

Denote is a simple note-taking tool.  It is based on the idea that notes
should follow a predictable and descriptive file-naming scheme.  The
file name must offer a clear indication of what the note is about,
without reference to any other metadata.  Denote basically streamlines
the creation of such files.

* The file-naming scheme
:PROPERTIES:
:CUSTOM_ID: h:4e9c7512-84dc-4dfb-9fa9-e15d51178e5d
:END:

Every note produced by Denote follows this pattern:

: DATE--TITLE--KEYWORDS.EXTENSION

The =DATE= field represents the date in year-month-day format followed
by the capital letter =T= (for "time") and the current time in
hour-minute-second notation.  The presentation is compact:
=20220531T091625=.  The =DATE= serves as the unique identifier of each
note.

The =TITLE= field is the title of the note, as provided by the user,
that automatically gets downcased and hyphenated.  An entry about
"Economics in the Euro Area" produces an =economics-in-the-euro-area=
string for the =TITLE= of the file name.

The =KEYWORDS= field consists of one or more entries demarcated by a
plus sign (the separator is inserted automatically).  Each keyword is a
string provided by the user at the relevant prompt which broadly
describes the contents of the entry.  Keywords that need to be more than
one-word-long must be written with an underscore.  So when
=emacs_library= appears in a file name, it is interpreted as a single
keyword, whereas =emacs+library= are two distinct keywords.

#+vindex: denote-file-type
The =EXTENSION= is the file type.  By default, it is =.org= (~org-mode~)
though the user option ~denote-file-type~ provides support for Markdown
(=.md= which runs ~markdown-mode~) and plain text (=.txt.= via
~text-mode~).  Consult its doc string for the minutia.

Examples:

: 20220107T124941--plentiful-and-predictable-liquidity--economics.org
: 20220214T104945--git-patch-formatting--emacs+git.md
: 20220420T113805--this-is-a-test--three_word_keyword.txt

While files end in the =.org= extension by default, the Denote code base
does not actually depend on org.el and/or its accoutrements.

#+vindex: denote-directory
Notes are stored as a flat list in the ~denote-directory~ (i.e. no
subdirectories).  The default path is =~/Documents/notes=.

* Points of entry
:PROPERTIES:
:CUSTOM_ID: h:17896c8c-d97a-4faa-abf6-31df99746ca6
:END:

#+findex: denote
#+findex: denote-org-capture
There are two ways to write a note with Denote: invoke the ~denote~
command or leverage the ~org-capture-templates~ by setting up a template
which calls the function ~denote-org-capture~.

In the first case, all that is needed is to run ~denote~.  It will first
prompt for a title.  Once it is supplied, the command will ask for
keywords.  The resulting note will have a file name as already explained
([[#h:4e9c7512-84dc-4dfb-9fa9-e15d51178e5d][The file naming scheme]]).

#+vindex: denote-known-keywords
#+vindex: denote-infer-keywords
The keyword prompt supports minibuffer completion.  Available candidates
are those defined in the user option ~denote-known-keywords~.  More
candidates can be inferred from the names of existing notes, by setting
~denote-infer-keywords~ to non-nil (which is the case by default).

#+vindex: denote-sort-keywords
Multiple keywords can be inserted by separating them with a comma (or
whatever the value of the ~crm-indicator~ is---which should be a comma).
When the user option ~denote-sort-keywords~ is non-nil (the default),
keywords are sorted alphabetically (technically, the sorting is done
with ~string-lessp~).

The ~denote~ command can also be called from Lisp, in which case it
expects the =TITLE= and =KEYWORDS= arguments.  The former is a string,
the latter a list of strings.

For integration with ~org-capture~, the user must first add the relevant
template.  Such as:

#+begin_src emacs-lisp
(with-eval-after-load 'org-capture
  (require 'denote-org-capture)
  (add-to-list 'org-capture-templates
               '("n" "New note (with Denote)" plain
                 (file denote-last-path)
                 #'denote-org-capture
                 :no-save t
                 :immediate-finish nil
                 :kill-buffer t
                 :jump-to-captured t)))
#+end_src

[ In the future, we might develop Denote in ways which do not require such
  manual intervation. ]

Once the template is added, it is accessed from the specified key.  If,
for instance, ~org-capture~ is bound to =C-c c=, then the note creation
is initiated with =C-c c n=.  After that, the process is the same as
with invoking ~denote~ directly, namely: a prompt for a title followed
by a prompt for keywords.

#+vindex: denote-org-capture-specifiers
Users may prefer to leverage ~org-capture~ in order to extend file
creation with the specifiers described in the ~org-capture-templates~
documentation (such as to capture the active region and/or create a
hyperlink pointing to the given context).  Due to the particular
file-naming scheme of Denote, such specifiers cannot be written directly
in the template.  Instead, they have to be assigned to the user option
~denote-org-capture-specifiers~, which is interpreted by the function
~denote-org-capture~.  Example with our default value:

#+begin_src emacs-lisp
(setq denote-org-capture-specifiers "%l\n%i\n%?")
#+end_src

Notes have their own "front matter".  This is a block of data at the top
of the file, which is automatically generated once producing a new
note. The front matter includes the title and keywords which the user
specified at the relevant prompts, as well as the date, the unique
identifier and the file path.  To ensure compatibility with the wider
Org ecosystem, the keywords are recorded as the value of =#+filetags=.

#+vindex: denote-front-matter-date-format
The format of the date in the front matter is controlled by the user
option ~denote-front-matter-date-format~:

- When the value is nil (the default), the date uses a plain
 =YEAR-MONTH-DAY= notation, like =2022-06-08=.
- When the value is the =org-timestamp= symbol, the date is recorded as
  an inactive Org timestamp, such as =[2022-06-08 Wed 06:19]=.
- An arbitrary string value is interpreted as the argument for the
  function ~format-time-string~.  This gives the user maximum control
  over how time is represented in the front matter.

* Linking notes
:PROPERTIES:
:CUSTOM_ID: h:fc913d54-26c8-4c41-be86-999839e8ad31
:END:

#+findex: denote-link
Denote has a basic linking facility to quickly establish connections
between notes.  The command ~denote-link~ prompts for a file name in the
~denote-directory~ (only regular files are considered, not directories).
It then retrieves the path of the given note, inserts it at point using
the appropriate link notation, and creates a backlink entry in the
target file (again using the appropriate notation).

What constitutes "appropriate link notation" depends on the file type of
the given entry per ~denote-file-type~ ([[#h:4e9c7512-84dc-4dfb-9fa9-e15d51178e5d][The file naming scheme]]).  For
example when linking from an Org file to a Markdown file, the link in
the former will follow Org syntax while the backlink in the latter will
use that of Markdown.  Org links use =[[file:TARGET][DESCRIPTION]]=,
those of Markdown are =[DESCRIPTION](file:TARGET)=, while for plain text
we implement our own scheme of =<TYPE: TARGET> [DESCRIPTION]=, where
=TYPE= is either =LINK= or =BACKLINK= (capitalization in the latter two
is literal, because plain text lacks other means of emphasis).

Plain text links can benefit from Emacs' notion of "future history",
else its ability to read the thing at point for relevant commands.  With
point over the =TARGET=, =M-x find-file= followed by =M-n= will fill the
path to that file (this also works with point over just the identifier
of a note).

Backlinks are recorded at the end of a note under the heading with the
title =Denote backlinks=.  Users should not edit the note below this
part manually: it is controlled by Denote, such as to delete duplicate
links (in the future it might also handle stuff like alphabetic
sorting).

The section with the backlinks is formatted according to the note's file
type.

#+vindex: denote-link-insert-functions
#+findex: denote-link-backlink
The special hook ~denote-link-insert-functions~ is called after a link
is created.  It accepts two arguments for the target file and the
formatted backlink to the original file.  The function
~denote-link-backlink~ provides an example for advanced users.

#+findex: denote-link-clear-stale-backlinks
Backlinks that no longer point to available notes can be removed from
the current buffer with the command ~denote-link-clear-stale-backlinks~.

* Fontification in Dired
:PROPERTIES:
:CUSTOM_ID: h:337f9cf0-9f66-45af-b73f-f6370472fb51
:END:

One of the upsides of Denote's file-naming scheme is the predictable
pattern it establishes, which appears as a near-tabular presentation in
a listing of notes (i.e. in Dired).  The ~denote-dired-mode~ can help
enhance this impression, by fontifying the components of the file name
to make the date (identifier) and keywords stand out.

There are two ways to set the mode.  Either use it for all directories,
which probably is not needed:

#+begin_src emacs-lisp
(require 'denote-dired)
(add-hook 'dired-mode-hook #'denote-dired-mode)
#+end_src

#+vindex: denote-dired-directories
#+findex: denote-dired-mode-in-directories
Or configure the user option ~denote-dired-directories~ and then set up
the function ~denote-dired-mode-in-directories~:

#+begin_src emacs-lisp
(require 'denote-dired)

;; We use different ways to specify a path for demo purposes.
(setq denote-dired-directories
      (list denote-directory
            (thread-last denote-directory (expand-file-name "attachments"))
            (expand-file-name "~/Documents/vlog")))

(add-hook 'dired-mode-hook #'denote-dired-mode-in-directories)
#+end_src

The ~denote-dired-mode~ does not only fontify note files that were
created by Denote: it covers every file name that follows our naming
conventions ([[#h:4e9c7512-84dc-4dfb-9fa9-e15d51178e5d][The file-naming scheme]]).  This is particularly useful for
scenaria where, say, one wants to organise their collection of PDFs and
multimedia in a systematic way (and, perhaps, use them as attachments
for the notes Denote produces).

For the time being, the =diredfl= package is not compatible with this
facility.

* Renaming non-notes
:PROPERTIES:
:CUSTOM_ID: h:532e8e2a-9b7d-41c0-8f4b-3c5cbb7d4dca
:END:

Denote's file-naming scheme is not specific to notes or text files: it
is useful for all sorts of files, such as multimedia and PDFs that form
part of the user's longer-term storage ([[#h:4e9c7512-84dc-4dfb-9fa9-e15d51178e5d][The file-naming scheme]]).  While
Denote does not manage such files, it already has all the mechanisms to
facilitate the task of renaming them.

#+findex: denote-dired-rename-file
To this end, invoke ~denote-dired-rename-file~ when point is over a file
in Dired to rename it.  The commaand prompts for a =TITLE= and
=KEYWORDS= the same way the ~denote~ command does it ([[#h:17896c8c-d97a-4faa-abf6-31df99746ca6][Points of entry]]).
It finally asks for confirmation before renaming the file at point.

The file type extension (e.g. =.pdf=) is read from the underlying file
and is preserved in the renaming process.  Files that have no extension
are simply left without one.

Renaming only occurs relative to the current directory.  Files are not
moved between directories.

* Extending Denote
:PROPERTIES:
:CUSTOM_ID: h:8ed2bb6f-b5be-4711-82e9-8bee5bb06ece
:END:

Denote is a tool with a narrow scope: create notes and link between
them, based on the aforementioned file-naming scheme.  For other common
operations the user is advised to rely on standard Emacs facilities or
specialised third-party packages.

- To search through notes, use =M-x grep=, =M-x find-name-dired=, =M-x
  consult-find=, =M-x consult-grep=, and so on (the latter two are
  provided by the =consult= package).

- To quickly jump to the ~denote-directory~, visit it with =M-x
  find-file= and then make a bookmark with =M-x bookmark-set=.  Access
  bookmarks with =M-x bookmark-jump=, =M-x consult-buffer= (from
 =consult=), and the like.

- Control the versioning of notes by turning the ~denote-directory~ into
  a Git project.  Consider the built-in project.el or the =projectile=
  package, as well as the built-in VC framework and/or the =magit=
  package.

- It is possible to narrow the list of notes in Dired using a regular
  expression or literal string.  Do =M-x dired-mark-files-regexp RET
  type-regexp-here RET t k=.  The =t= will toggle the match so that it
  marks all files that do not match the regexp and =k= will remove them
  from the buffer (restore them by reverting the buffer).

- A narrowed list of files can also be produced through the minibuffer,
  with the help of the =embark= package.  For example, =M-x find-file
  RET path/to/denote-directory RET regexp embark-act embark-export=.
  The final two commands, ~embark-act~ and ~embark-export~, are normally
  bound to keys.  The whole sequence will thus look like =C-x C-f path
  RET regexp C-. E=.

* Installation
:PROPERTIES:
:CUSTOM_ID: h:f3bdac2c-4704-4a51-948c-a789a2589790
:END:
#+cindex: Installation instructions

** COMMENT GNU ELPA package
:PROPERTIES:
:CUSTOM_ID: h:42953f87-82bd-43ec-ab99-22b1e22955e7
:END:

The package is available as =logos=.  Simply do:

: M-x package-refresh-contents
: M-x package-install

And search for it.

GNU ELPA provides the latest stable release.  Those who prefer to follow
the development process in order to report bugs or suggest changes, can
use the version of the package from the GNU-devel ELPA archive.  Read:
https://protesilaos.com/codelog/2022-05-13-emacs-elpa-devel/.

** Manual installation
:PROPERTIES:
:CUSTOM_ID: h:d397712c-c8c0-4cfa-ad1a-ef28cf78d1f0
:END:

Assuming your Emacs files are found in =~/.emacs.d/=, execute the
following commands in a shell prompt:

#+begin_src sh
cd ~/.emacs.d

# Create a directory for manually-installed packages
mkdir manual-packages

# Go to the new directory
cd manual-packages

# Clone this repo, naming it "denote"
git clone https://git.sr.ht/~protesilaos/denote denote
#+end_src

Finally, in your =init.el= (or equivalent) evaluate this:

#+begin_src emacs-lisp
;; Make Elisp files in that directory available to the user.
(add-to-list 'load-path "~/.emacs.d/manual-packages/denote")
#+end_src

Everything is in place to set up the package.

* Sample configuration
:PROPERTIES:
:CUSTOM_ID: h:5d16932d-4f7b-493d-8e6a-e5c396b15fd6
:END:
#+cindex: Package configuration

#+begin_src emacs-lisp
(require 'denote)

;; Remember to check the doc strings of those variables.
(setq denote-directory (expand-file-name "~/Documents/notes/"))
(setq denote-known-keywords
      '("emacs" "philosophy" "politics" "economics"))
(setq denote-infer-keywords t)
(setq denote-sort-keywords t)
(setq denote-file-type nil) ; default is Org mode, else set `markdown' or `text'

(setq denote-front-matter-date-format 'org-timestamp)

(require 'denote-link)
(require 'denote-dired)

;; We use different ways to specify a path for demo purposes.
(setq denote-dired-directories
      (list denote-directory
            (thread-last denote-directory (expand-file-name "attachments"))
            (expand-file-name "~/Documents/vlog")))

;; Generic:
;; (add-hook 'dired-mode-hook #'denote-dired-mode)
;;
;; OR better:
(add-hook 'dired-mode-hook #'denote-dired-mode-in-directories)

;; You can bind `denote' to a global key if you prefer not to use
;; `org-capture' or want an alternative.  For example:
(define-key global-map (kbd "C-c n") #'denote)

(with-eval-after-load 'org-capture
  (require 'denote-org-capture)
  (setq denote-org-capture-specifiers "%l\n%i\n%?")
  (add-to-list 'org-capture-templates
               '("n" "New note (with denote.el)" plain
                 (file denote-last-path)
                 #'denote-org-capture
                 :no-save t
                 :immediate-finish nil
                 :kill-buffer t
                 :jump-to-captured t))))
#+end_src

* Acknowledgements
:PROPERTIES:
:CUSTOM_ID: h:f8126820-3b59-49fa-bcc2-73bd60132bb9
:END:
#+cindex: Contributors

Denote is meant to be a collective effort.  Every bit of help matters.

+ Author/maintainer :: Protesilaos Stavrou.

+ Contributions to code or the manual :: Jack Baty, Kaushal Modi.

+ Ideas and/or user feedback :: Kaushal Modi, Ypot.

* GNU Free Documentation License
:PROPERTIES:
:APPENDIX: t
:CUSTOM_ID: h:2d84e73e-c143-43b5-b388-a6765da974ea
:END:

#+texinfo: @include doclicense.texi

#+begin_export html
<pre>

                GNU Free Documentation License
                 Version 1.3, 3 November 2008


 Copyright (C) 2000, 2001, 2002, 2007, 2008 Free Software Foundation, Inc.
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 Everyone is permitted to copy and distribute verbatim copies
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printed covers) of the Document, numbering more than 100, and the
Document's license notice requires Cover Texts, you must enclose the
copies in covers that carry, clearly and legibly, all these Cover
Texts: Front-Cover Texts on the front cover, and Back-Cover Texts on
the back cover.  Both covers must also clearly and legibly identify
you as the publisher of these copies.  The front cover must present
the full title with all words of the title equally prominent and
visible.  You may add other material on the covers in addition.
Copying with changes limited to the covers, as long as they preserve
the title of the Document and satisfy these conditions, can be treated
as verbatim copying in other respects.

If the required texts for either cover are too voluminous to fit
legibly, you should put the first ones listed (as many as fit
reasonably) on the actual cover, and continue the rest onto adjacent
pages.

If you publish or distribute Opaque copies of the Document numbering
more than 100, you must either include a machine-readable Transparent
copy along with each Opaque copy, or state in or with each Opaque copy
a computer-network location from which the general network-using
public has access to download using public-standard network protocols
a complete Transparent copy of the Document, free of added material.
If you use the latter option, you must take reasonably prudent steps,
when you begin distribution of Opaque copies in quantity, to ensure
that this Transparent copy will remain thus accessible at the stated
location until at least one year after the last time you distribute an
Opaque copy (directly or through your agents or retailers) of that
edition to the public.

It is requested, but not required, that you contact the authors of the
Document well before redistributing any large number of copies, to
give them a chance to provide you with an updated version of the
Document.


4. MODIFICATIONS

You may copy and distribute a Modified Version of the Document under
the conditions of sections 2 and 3 above, provided that you release
the Modified Version under precisely this License, with the Modified
Version filling the role of the Document, thus licensing distribution
and modification of the Modified Version to whoever possesses a copy
of it.  In addition, you must do these things in the Modified Version:

A. Use in the Title Page (and on the covers, if any) a title distinct
   from that of the Document, and from those of previous versions
   (which should, if there were any, be listed in the History section
   of the Document).  You may use the same title as a previous version
   if the original publisher of that version gives permission.
B. List on the Title Page, as authors, one or more persons or entities
   responsible for authorship of the modifications in the Modified
   Version, together with at least five of the principal authors of the
   Document (all of its principal authors, if it has fewer than five),
   unless they release you from this requirement.
C. State on the Title page the name of the publisher of the
   Modified Version, as the publisher.
D. Preserve all the copyright notices of the Document.
E. Add an appropriate copyright notice for your modifications
   adjacent to the other copyright notices.
F. Include, immediately after the copyright notices, a license notice
   giving the public permission to use the Modified Version under the
   terms of this License, in the form shown in the Addendum below.
G. Preserve in that license notice the full lists of Invariant Sections
   and required Cover Texts given in the Document's license notice.
H. Include an unaltered copy of this License.
I. Preserve the section Entitled "History", Preserve its Title, and add
   to it an item stating at least the title, year, new authors, and
   publisher of the Modified Version as given on the Title Page.  If
   there is no section Entitled "History" in the Document, create one
   stating the title, year, authors, and publisher of the Document as
   given on its Title Page, then add an item describing the Modified
   Version as stated in the previous sentence.
J. Preserve the network location, if any, given in the Document for
   public access to a Transparent copy of the Document, and likewise
   the network locations given in the Document for previous versions
   it was based on.  These may be placed in the "History" section.
   You may omit a network location for a work that was published at
   least four years before the Document itself, or if the original
   publisher of the version it refers to gives permission.
K. For any section Entitled "Acknowledgements" or "Dedications",
   Preserve the Title of the section, and preserve in the section all
   the substance and tone of each of the contributor acknowledgements
   and/or dedications given therein.
L. Preserve all the Invariant Sections of the Document,
   unaltered in their text and in their titles.  Section numbers
   or the equivalent are not considered part of the section titles.
M. Delete any section Entitled "Endorsements".  Such a section
   may not be included in the Modified Version.
N. Do not retitle any existing section to be Entitled "Endorsements"
   or to conflict in title with any Invariant Section.
O. Preserve any Warranty Disclaimers.

If the Modified Version includes new front-matter sections or
appendices that qualify as Secondary Sections and contain no material
copied from the Document, you may at your option designate some or all
of these sections as invariant.  To do this, add their titles to the
list of Invariant Sections in the Modified Version's license notice.
These titles must be distinct from any other section titles.

You may add a section Entitled "Endorsements", provided it contains
nothing but endorsements of your Modified Version by various
parties--for example, statements of peer review or that the text has
been approved by an organization as the authoritative definition of a
standard.

You may add a passage of up to five words as a Front-Cover Text, and a
passage of up to 25 words as a Back-Cover Text, to the end of the list
of Cover Texts in the Modified Version.  Only one passage of
Front-Cover Text and one of Back-Cover Text may be added by (or
through arrangements made by) any one entity.  If the Document already
includes a cover text for the same cover, previously added by you or
by arrangement made by the same entity you are acting on behalf of,
you may not add another; but you may replace the old one, on explicit
permission from the previous publisher that added the old one.

The author(s) and publisher(s) of the Document do not by this License
give permission to use their names for publicity for or to assert or
imply endorsement of any Modified Version.


5. COMBINING DOCUMENTS

You may combine the Document with other documents released under this
License, under the terms defined in section 4 above for modified
versions, provided that you include in the combination all of the
Invariant Sections of all of the original documents, unmodified, and
list them all as Invariant Sections of your combined work in its
license notice, and that you preserve all their Warranty Disclaimers.

The combined work need only contain one copy of this License, and
multiple identical Invariant Sections may be replaced with a single
copy.  If there are multiple Invariant Sections with the same name but
different contents, make the title of each such section unique by
adding at the end of it, in parentheses, the name of the original
author or publisher of that section if known, or else a unique number.
Make the same adjustment to the section titles in the list of
Invariant Sections in the license notice of the combined work.

In the combination, you must combine any sections Entitled "History"
in the various original documents, forming one section Entitled
"History"; likewise combine any sections Entitled "Acknowledgements",
and any sections Entitled "Dedications".  You must delete all sections
Entitled "Endorsements".


6. COLLECTIONS OF DOCUMENTS

You may make a collection consisting of the Document and other
documents released under this License, and replace the individual
copies of this License in the various documents with a single copy
that is included in the collection, provided that you follow the rules
of this License for verbatim copying of each of the documents in all
other respects.

You may extract a single document from such a collection, and
distribute it individually under this License, provided you insert a
copy of this License into the extracted document, and follow this
License in all other respects regarding verbatim copying of that
document.


7. AGGREGATION WITH INDEPENDENT WORKS

A compilation of the Document or its derivatives with other separate
and independent documents or works, in or on a volume of a storage or
distribution medium, is called an "aggregate" if the copyright
resulting from the compilation is not used to limit the legal rights
of the compilation's users beyond what the individual works permit.
When the Document is included in an aggregate, this License does not
apply to the other works in the aggregate which are not themselves
derivative works of the Document.

If the Cover Text requirement of section 3 is applicable to these
copies of the Document, then if the Document is less than one half of
the entire aggregate, the Document's Cover Texts may be placed on
covers that bracket the Document within the aggregate, or the
electronic equivalent of covers if the Document is in electronic form.
Otherwise they must appear on printed covers that bracket the whole
aggregate.


8. TRANSLATION

Translation is considered a kind of modification, so you may
distribute translations of the Document under the terms of section 4.
Replacing Invariant Sections with translations requires special
permission from their copyright holders, but you may include
translations of some or all Invariant Sections in addition to the
original versions of these Invariant Sections.  You may include a
translation of this License, and all the license notices in the
Document, and any Warranty Disclaimers, provided that you also include
the original English version of this License and the original versions
of those notices and disclaimers.  In case of a disagreement between
the translation and the original version of this License or a notice
or disclaimer, the original version will prevail.

If a section in the Document is Entitled "Acknowledgements",
"Dedications", or "History", the requirement (section 4) to Preserve
its Title (section 1) will typically require changing the actual
title.


9. TERMINATION

You may not copy, modify, sublicense, or distribute the Document
except as expressly provided under this License.  Any attempt
otherwise to copy, modify, sublicense, or distribute it is void, and
will automatically terminate your rights under this License.

However, if you cease all violation of this License, then your license
from a particular copyright holder is reinstated (a) provisionally,
unless and until the copyright holder explicitly and finally
terminates your license, and (b) permanently, if the copyright holder
fails to notify you of the violation by some reasonable means prior to
60 days after the cessation.

Moreover, your license from a particular copyright holder is
reinstated permanently if the copyright holder notifies you of the
violation by some reasonable means, this is the first time you have
received notice of violation of this License (for any work) from that
copyright holder, and you cure the violation prior to 30 days after
your receipt of the notice.

Termination of your rights under this section does not terminate the
licenses of parties who have received copies or rights from you under
this License.  If your rights have been terminated and not permanently
reinstated, receipt of a copy of some or all of the same material does
not give you any rights to use it.


10. FUTURE REVISIONS OF THIS LICENSE

The Free Software Foundation may publish new, revised versions of the
GNU Free Documentation License from time to time.  Such new versions
will be similar in spirit to the present version, but may differ in
detail to address new problems or concerns.  See
https://www.gnu.org/licenses/.

Each version of the License is given a distinguishing version number.
If the Document specifies that a particular numbered version of this
License "or any later version" applies to it, you have the option of
following the terms and conditions either of that specified version or
of any later version that has been published (not as a draft) by the
Free Software Foundation.  If the Document does not specify a version
number of this License, you may choose any version ever published (not
as a draft) by the Free Software Foundation.  If the Document
specifies that a proxy can decide which future versions of this
License can be used, that proxy's public statement of acceptance of a
version permanently authorizes you to choose that version for the
Document.

11. RELICENSING

"Massive Multiauthor Collaboration Site" (or "MMC Site") means any
World Wide Web server that publishes copyrightable works and also
provides prominent facilities for anybody to edit those works.  A
public wiki that anybody can edit is an example of such a server.  A
"Massive Multiauthor Collaboration" (or "MMC") contained in the site
means any set of copyrightable works thus published on the MMC site.

"CC-BY-SA" means the Creative Commons Attribution-Share Alike 3.0
license published by Creative Commons Corporation, a not-for-profit
corporation with a principal place of business in San Francisco,
California, as well as future copyleft versions of that license
published by that same organization.

"Incorporate" means to publish or republish a Document, in whole or in
part, as part of another Document.

An MMC is "eligible for relicensing" if it is licensed under this
License, and if all works that were first published under this License
somewhere other than this MMC, and subsequently incorporated in whole or
in part into the MMC, (1) had no cover texts or invariant sections, and
(2) were thus incorporated prior to November 1, 2008.

The operator of an MMC Site may republish an MMC contained in the site
under CC-BY-SA on the same site at any time before August 1, 2009,
provided the MMC is eligible for relicensing.


ADDENDUM: How to use this License for your documents

To use this License in a document you have written, include a copy of
the License in the document and put the following copyright and
license notices just after the title page:

    Copyright (c)  YEAR  YOUR NAME.
    Permission is granted to copy, distribute and/or modify this document
    under the terms of the GNU Free Documentation License, Version 1.3
    or any later version published by the Free Software Foundation;
    with no Invariant Sections, no Front-Cover Texts, and no Back-Cover Texts.
    A copy of the license is included in the section entitled "GNU
    Free Documentation License".

If you have Invariant Sections, Front-Cover Texts and Back-Cover Texts,
replace the "with...Texts." line with this:

    with the Invariant Sections being LIST THEIR TITLES, with the
    Front-Cover Texts being LIST, and with the Back-Cover Texts being LIST.

If you have Invariant Sections without Cover Texts, or some other
combination of the three, merge those two alternatives to suit the
situation.

If your document contains nontrivial examples of program code, we
recommend releasing these examples in parallel under your choice of
free software license, such as the GNU General Public License,
to permit their use in free software.
</pre>
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