Speedbar is a program for Emacs which can be used to summarize information related to the current buffer. Its original inspiration is the “explorer” often used in modern development environments, office packages, and web browsers.
Speedbar displays a narrow frame in which a tree view is shown. This tree view defaults to containing a list of files and directories. Files can be “expanded” to list tags inside. Directories can be expanded to list the files within them. Each file or tag can be jumped to immediately.
Speedbar expands upon “explorer” windows by maintaining context with the user. For example, when using the file view, the current buffer’s file is highlighted. Speedbar also mimics the explorer windows by providing multiple display modes. These modes come in two flavors. Major display modes remain consistent across buffers, and minor display modes appear only when a buffer of the applicable type is shown. This allows authors of other packages to provide speedbar summaries customized to the needs of that mode.
Throughout this manual, activities are defined as “clicking on”, or “expanding” items. Clicking means using mouse-2 on a button. Expanding refers to clicking on an expansion button to display an expanded summary of the entry the expansion button is on. See Basic Navigation.
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To start using speedbar use the command M-x speedbar RET or select it from the ‘Options->Show/Hide’ sub-menu. This command will open a new frame to summarize the local files. On X Window systems or on MS-Windows, speedbar’s frame is twenty characters wide, and will mimic the height of the frame from which it was started. It positions itself to the left or right of the frame you started it from.
To use speedbar effectively, it is important to understand its relationship with the frame you started it from. This frame is the attached frame which speedbar will use as a reference point. Once started, speedbar watches the contents of this frame, and attempts to make its contents relevant to the buffer loaded into the attached frame. In addition, all requests made in speedbar that require the display of another buffer will display in the attached frame.
When used in terminal mode, the new frame appears the same size as the terminal. Since it is not visible while working in the attached frame, speedbar will save time by using the slowbar mode, where no tracking is done until speedbar is requested to show itself (i.e., the speedbar’s frame becomes the selected frame).
The function to use when switching between frames using the keyboard is
speedbar-get-focus
. This function will toggle between frames, and
it’s useful to bind it to a key in terminal mode. See Customizing.
File mode displays a summary of your current directory. You can display files in the attached frame, or summarize the tags found in files. You can even see if a file is checked out of a version control system, or has some associated object file.
Advanced behavior, like copying and renaming files, is also provided.
There are three major sections in the display. The first line or two is the root directory speedbar is currently viewing. You can jump to one of the parent directories by clicking on the name of the directory you wish to jump to.
Next, directories are listed. A directory starts with the group indicator button ‘<+>’. Clicking the directory name makes speedbar load that directory as the root directory for its display. Clicking the ‘<+>’ button will list all directories and files beneath.
Next, files are listed. Files start with the group indicator ‘[+]’ or ‘[?]’. You can jump to a file in the attached frame by clicking on the file name. You can expand a file and look at its tags by clicking on the ‘[+]’ symbol near the file name.
A typical session might look like this:
~/lisp/ <+> checkdoc <+> eieio <-> speedbar [+] Makefile [+] rpm.el # [+] sb-gud.el # [+] sb-info.el # [+] sb-rmail.el # [+] sb-w3.el [-] speedbar.el *! {+} Types {+} Variables {+} def (group) {+} speedbar- [+] speedbar.texi * <+> testme [+] align.el [+] autoconf.el
In this example, you can see several directories. The directory speedbar has been opened inline. Inside the directory speedbar, the file speedbar.el has its tags exposed. These tags are extensive, and they are summarized into tag groups.
Files get additional boolean flags associated with them. Valid flags are:
*
This file has been checked out of a version control system. See Version Control.
#
This file has an up to date object file associated with it. The
variable speedbar-obj-alist
defines how speedbar determines this
value.
!
This file has an out of date object file associated with it.
A Tag group is prefixed with the symbol ‘{+}’. Clicking this
symbol will show all symbols that have been organized into that group.
Different types of files have unique tagging methods as defined by their
major mode. Tags are generated with either the imenu
package, or
through the etags
interface.
Tag groups are defined in multiple ways which make it easier to find the tag you are looking for. Imenu keywords explicitly create groups, and speedbar will automatically create groups if tag lists are too long.
In our example, Imenu created the groups ‘Types’ and
‘Variables’. All remaining top-level symbols are then regrouped
based on the variable speedbar-tag-hierarchy-method
. The
subgroups ‘def’ and ‘speedbar-’ are groupings where the first
few characters of the given symbols are specified in the group name.
Some group names may say something like ‘speedbar-t to speedbar-v’,
indicating that all symbols which alphabetically fall between those
categories are included in that sub-group. See Tag Hierarchy Methods.
On GNU and Unix systems, a hidden file is a file whose name starts with a period. They are hidden from a regular directory listing because the user is not generally interested in them.
In speedbar, a hidden file is a file which isn’t very interesting and
might prove distracting to the user. Any uninteresting files are
removed from the File display. There are two levels of uninterest in
speedbar. The first level of uninterest are files which have no
expansion method, or way of extracting tags. The second level is any
file that matches the same pattern used for completion in
find-file
. This is derived from the variable
completion-ignored-extensions
.
You can toggle the display of uninteresting files from the toggle menu item ‘Show All Files’. This will display all level one hidden files. These files will be shown with a ‘?’ indicator. Level 2 hidden files will still not be shown.
Object files fall into the category of level 2 hidden files. You can determine their presence by the ‘#’ and ‘!’ file indicators. See Directory Display.
File mode has key bindings permitting different file system operations such as copy or rename. These commands all operate on the current file. In this case, the current file is the file at point, or clicked on when pulling up the menu.
Move the entire speedbar display up one directory.
Display information in the minibuffer about this line. This is the same information shown when navigating with n and p, or moving the mouse over an item.
Byte compile the Emacs Lisp file on this line.
Load the Emacs Lisp file on this line. If a .elc file exists, optionally load that.
Copy the current file to some other location.
Rename the current file, possibly moving it to some other location.
Delete the current file.
Delete the current file’s object file. Use the symbols ‘#’ and ‘!’ to determine if there is an object file available.
One menu item toggles the display of all available files. By default, only files which Emacs understands, and knows how to convert into a tag list, are shown. By showing all files, additional files such as text files are also displayed, but they are prefixed with the ‘[?]’ symbol. This means that it is a file, but Emacs doesn’t know how to expand it.
Buffer mode is very similar to File mode, except that instead of tracking the current directory and all files available there, the current list of Emacs buffers is shown.
These buffers can have their tags expanded in the same way as files, and uses the same unknown file indicator (see File Mode).
Buffer mode does not have file operation bindings, but the following buffer specific key bindings are available:
Kill this buffer. Do not touch its file.
Revert this buffer, reloading from disk.
In addition to Buffer mode, there is also Quick Buffer mode. In fact, Quick Buffers is bound to the b key. The only difference between Buffers and Quick Buffers is that after one operation is performed which affects the attached frame, the display is immediately reverted to the last displayed mode.
Thus, if you are in File mode, and you need quick access to a buffer, press b, click on the buffer you want, and speedbar will revert back to File mode.
For some buffers, a list of files and tags makes no sense. This could be because files are not currently in reference (such as web pages), or that the files you might be interested have special properties (such as email folders.)
In these cases, a minor display mode is needed. A minor display mode will override any major display mode currently being displayed for the duration of the specialized buffer’s use. Minor display modes will follow the general rules of their major counterparts in terms of key bindings and visuals, but will have specialized behaviors.
When using RMAIL, speedbar will display two sections. The first is a layer one reply button. Clicking here will initialize a reply buffer showing only this email address in the ‘To:’ field.
The second section lists all RMAIL folders in the same directory as your main RMAIL folder. The general rule is that RMAIL folders always appear in all caps, or numbers. It is possible to save mail in folders with lower case letters, but there is no clean way of detecting such RMAIL folders without opening them all.
Each folder can be visited by clicking the name. You can move mail from the current RMAIL folder into a different folder by clicking the ‘<M>’ button. The ‘M’ stands for Move.
In this way you can manage your existing RMAIL folders fairly easily using the mouse.
When browsing Info files, all local relevant information is displayed in the info buffer and a topical high-level view is provided in speedbar. All top-level info nodes are shown in the speedbar frame, and can be jumped to by clicking the name.
You can open these nodes with the ‘[+]’ button to see what sub-topics are available. Since these sub-topics are not examined until you click the ‘[+]’ button, sometimes a ‘[?]’ will appear when you click on a ‘[+]’, indicating that there are no sub-topics.
You can debug an application with GDB in Emacs using graphical mode or text command mode (see GDB Graphical Interface in The extensible self-documenting text editor).
If you are using graphical mode you can see how selected variables change each time your program stops (see Watch Expressions in The extensible self-documenting text editor).
If you are using text command mode, speedbar can show you the current stack when the current buffer is the *gdb* buffer. Usually, it will just report that there is no stack, but when the application is stopped, the current stack will be shown.
You can click on any stack element and gdb will move to that stack level. You can then check variables local to that level at the GDB prompt.
Speedbar is highly customizable, with a plethora of control elements. Since speedbar is so visual and reduces so much information, this is an important aspect of its behavior.
In general, there are three custom groups you can use to quickly modify speedbar’s behavior.
speedbar
Basic speedbar behaviors.
speedbar-vc
Customizations regarding version control handling.
speedbar-faces
Customize speedbar’s many colors and fonts.
There are several faces speedbar generates to provide a consistent color scheme across display types. You can customize these faces using your favorite method. They are:
Face used on Files. Should also be used on non-directory like nodes.
Face used for directories, or nodes which consist of groups of other nodes.
Face used to highlight the selected item. This would be the current file being edited.
Face used when the mouse passes over a button.
You can also customize speedbar’s initial frame parameters by changing
the alist speedbar-frame-parameters
. This variable is used to
set up initial details. Height is also automatically added when
speedbar is created, though you can override it.
When listing tags within a file, it is possible to get an annoyingly long list of entries. Imenu (which generates the tag list in Emacs) will group some classes of items automatically. Even here, however, some tag groups can be quite large.
To solve this problem, tags can be grouped into logical units through a
hierarchy processor. The specific variable to use is
speedbar-tag-hierarchy-method
. There are several methods that
can be applied in any order. They are:
speedbar-trim-words-tag-hierarchy
¶Find a common prefix for all elements of a group, and trim it off.
speedbar-prefix-group-tag-hierarchy
If a group is too large, place sets of tags into bins based on common prefixes.
speedbar-simple-group-tag-hierarchy
Take all items in the top level list not in a group, and stick them into a ‘Tags’ group.
speedbar-sort-tag-hierarchy
Sort all items, leaving groups on top.
You can also add your own functions to reorganize tags as you see fit.
Some other control variables are:
speedbar-tag-group-name-minimum-length
¶Default value: 4.
The minimum length of a prefix group name before expanding. Thus, if
the speedbar-tag-hierarchy-method
includes
speedbar-prefix-group-tag-hierarchy
and one such group’s common
characters is less than this number of characters, then the group name
will be changed to the form of:
worda to wordb
instead of just
word
This way we won’t get silly looking listings.
speedbar-tag-split-minimum-length
¶Default value: 20.
Minimum length before we stop trying to create sub-lists in tags. This is used by all tag-hierarchy methods that break large lists into sub-lists.
speedbar-tag-regroup-maximum-length
¶Default value: 10.
Maximum length of submenus that are regrouped. If the regrouping option is used, then if two or more short subgroups are next to each other, then they are combined until this number of items is reached.
When using the file mode in speedbar, information regarding a version control system adds small details to the display. If a file is in a version control system, and is “checked out” or “locked” locally, an asterisk ‘*’ appears at the end of the file name. In addition, the directory name for Version Control systems are left out of the speedbar display.
You can easily add new version control systems into speedbar’s detection
scheme. To make a directory “disappear” from the list, use the variable
speedbar-directory-unshown-regexp
.
Next, you need to write entries for two hooks. The first is
speedbar-vc-path-enable-hook
which will enable a VC check in the
current directory for the group of files being checked. Your hook
function should take one parameter (the directory to check) and return
t
if your VC method is in control here.
The second function is speedbar-vc-in-control-hook
. This hook
takes two parameters, the path of the file to check, and the
file name. Return t
if you want to have the asterisk
placed near this file.
Lastly, you can change the VC indicator using the variable
speedbar-vc-indicator
, and specify a single character string.
There are several hooks in speedbar allowing custom behaviors to be added. Available hooks are:
speedbar-visiting-file-hook
¶Hooks run when speedbar visits a file in the selected frame.
speedbar-visiting-tag-hook
speedbar-reconfigure-keymaps-hook
Hooks run when the keymaps are regenerated. Keymaps are reconfigured whenever modes change. This will let you add custom key bindings.
speedbar-before-popup-hook
Hooks called before popping up the speedbar frame. New frames are often popped up when “power clicking” on an item to view it.
speedbar-before-delete-hook
speedbar-mode-hook
speedbar-timer-hook
speedbar-scanner-reset-hook
Hook called whenever generic scanners are reset. Set this to implement your own scanning or rescan safe functions with state data.
Speedbar can run different types of Major display modes such as Files (see File Mode), and Buffers (see Buffer Mode). It can also manage different minor display modes for use with buffers handling specialized data.
These major and minor display modes are handled through an extension
system which permits specialized keymaps and menu extensions, in
addition to a unique rendering function. You can also specify a wide
range of tagging functions. The default uses imenu
, but new
tagging methods can be easily added. In this chapter, you will
learn how to write your own major or minor display modes, and how to
create specialized tagging functions.
A minor display mode is a mode useful when using a specific type of buffer. This mode might not be useful for any other kind of data or mode, or may just be more useful that a files or buffers based mode when working with a specialized mode.
Examples that already exist for speedbar include RMAIL, Info, and gdb. These modes display information specific to the major mode shown in the attached frame.
To enable a minor display mode in your favorite Major mode, follow these steps. The string ‘name’ is the name of the major mode being augmented with speedbar.
name-speedbar-mode-map
.
(setq name-speedbar-mode-map (speedbar-make-specialized-keymap))
This function creates a special keymap for use in speedbar.
(with-eval-after-load 'speedbar (name-install-speedbar-variables))
name-speedbar-menu-items
. This will be spliced into
speedbar’s control menu.
name-speedbar-buttons
. This function
should take one variable, which is the buffer for which it will create
buttons. At this time (current-buffer)
will point to the
uncleared speedbar buffer.
When writing name-speedbar-buttons
, the first thing you will
want to do is execute a check to see if you need to re-create your
display. If it needs to be cleared, you need to erase the speedbar
buffer yourself, and start drawing buttons. See Creating a display.
Creating a Major Display Mode for speedbar requires authoring a keymap, an easy-menu segment, and writing several functions. These items can be given any name, and are made the same way as in a minor display mode (see Minor Display Modes). Once this is done, these items need to be registered.
Because this setup activity may or may not have speedbar available when it is being loaded, it is necessary to create an install function. This function should create and initialize the keymap, and add your expansions into the customization tables.
When creating the keymap, use the function
speedbar-make-specialized-keymap
instead of other keymap making
functions. This will provide you with the initial bindings needed.
Some common speedbar functions you might want to bind are:
speedbar-edit-line
¶speedbar-expand-line
Expand the item under the cursor. With a numeric argument (C-u), flush cached data before expanding.
speedbar-contract-line
Contract the item under the cursor.
These functions require that the function speedbar-line-directory
be
correctly overloaded to work.
Next, register your extension like this;
(speedbar-add-expansion-list '("MyExtension" MyExtension-speedbar-menu-items MyExtension-speedbar-mode-map MyExtension-speedbar-buttons))
There are no limitations to the names you use.
The first parameter is the string representing your display mode. The second parameter is a variable name containing an easymenu compatible menu definition. This will be stuck in the middle of speedbar’s menu. The third parameter is the variable name containing the keymap we discussed earlier. The last parameter is a function which draws buttons for your mode. This function must take two parameters. The directory currently being displayed, and the depth at which you should start rendering buttons. The function will then draw (starting at the current cursor position) any buttons deemed necessary based on the input parameters. See Creating a display.
Next, you need to register function overrides. This may look something like this:
(speedbar-add-mode-functions-list '("MYEXTENSION" (speedbar-item-info . MyExtension-speedbar-item-info) (speedbar-line-directory . MyExtension-speedbar-line-directory)))
The first element in the list is the name of you extension. The second is an alist of functions to overload. The function to overload is first, followed by what you want called instead.
For speedbar-line-directory
your function should take an optional DEPTH
parameter. This is the starting depth for heavily indented lines. If
it is not provided, you can derive it like this:
(save-match-data (if (not depth) (progn (beginning-of-line) (looking-at "^\\([0-9]+\\):") (setq depth (string-to-number (match-string 1)))))
where the depth is stored as invisible text at the beginning of each line.
The path returned should be the full path name of the file associated with that line. If the cursor is on a tag, then the file containing that tag should be returned. This is critical for built in file based functions to work (meaning less code for you to write). If your display does not deal in files, you do not need to overload this function.
The function speedbar-item-info
, however, is very likely to need
overloading. This function takes no parameters and must derive a text
summary to display in the minibuffer.
There are several helper functions you can use if you are going to use
built in tagging. These functions can be or
ed since each one
returns non-nil
if it displays a message. They are:
speedbar-item-info-file-helper
¶This takes an optional filename parameter. You can derive your own
filename, or it will derive it using a (possibly overloaded) function
speedbar-line-file
. It shows details about a file.
speedbar-item-info-tag-helper
If the current line is a tag, then display information about that tag, such as its parent file, and location.
Your custom function might look like this:
(defun MyExtension-item-info () "Display information about the current line." (or (speedbar-item-info-tag-helper) (message "Interesting detail.")))
Once you have done all this, speedbar will show an entry in the ‘Displays’ menu declaring that your extension is available.
It is possible to create new methods for tagging files in speedbar. To do this, you need two basic functions, one function to fetch the tags from a buffer, the other to insert them below the filename.
Parse file for a list of tags. Return the list, or t
if there was
an error.
The non-error return value can be anything, as long as it can be inserted by its paired function:
Insert a list of tags lst started at indentation level level. Creates buttons for each tag, and provides any other display information required.
It is often useful to use speedbar-create-tag-hierarchy
on your
token list. See that function’s documentation for details on what it
requires.
Once these two functions are written, modify the variable
speedbar-dynamic-tags-function-list
to include your parser at the
beginning, like this:
(add-to-list 'speedbar-dynamic-tags-function-list '(my-fetch-dynamic-tags . my-insert-tag-list))
If your parser is only good for a few types of files, make sure that it
is either a buffer local modification, or that the tag generator returns
t
for non valid buffers.
Rendering a display in speedbar is completely flexible. When your
button function is called, see Minor Display Modes, and Major Display Modes, you have control to insert
anything you want.
The conventions allow almost anything to be inserted, but several helper functions are provided to make it easy to create the standardized buttons.
To understand the built in functions, each “button” in speedbar consists of four important pieces of data. The text to be displayed, token data to be associated with the text, a function to call, and some face to display it in.
When a function is provided, then that text becomes mouse activated, meaning the mouse will highlight the text.
Additionally, for data which can form deep trees, each line is given a depth which indicates how far down the tree it is. This information is stored in invisible text at the beginning of each line, and is used by the navigation commands.
This function inserts one button into the current location. text is the text to insert. face is the face in which it will be displayed. mouse is the face to display over the text when the mouse passes over it. function is called whenever the user clicks on the text.
The optional argument token is extra data to associated with the
text. Lastly prevline should be non-nil
if you want this line to
appear directly after the last button which was created instead of on
the next line.
Create a tag line with exp-button-type for the small expansion
button. This is the button that expands or contracts a node (if
applicable), and exp-button-char the character in it (‘+’,
‘-’, ‘?’, etc.). exp-button-function is the function
to call if it’s clicked on. Button types are bracket
,
angle
, curly
, expandtag
, statictag
, and
nil
. exp-button-data is extra data attached to the text
forming the expansion button.
Next, tag-button is the text of the tag. tag-button-function is the function to call if clicked on, and tag-button-data is the data to attach to the text field (such a tag positioning, etc.). tag-button-face is a face used for this type of tag.
Lastly, depth shows the depth of expansion.
This function assumes that the cursor is in the speedbar window at the position to insert a new item, and that the new item will end with a CR.
At level, (the current indentation level desired) insert a generic
multi-level alist list. Associations with lists get ‘{+}’
tags (to expand into more nodes) and those with positions or other data
just get a ‘>’ as the indicator. ‘{+}’ buttons will have the
function expand-fun and the token is the cdr
list. The
token name will have the function find-fun and not token.
Each element of the list can have one of these forms:
(name . marker-or-number)
One tag at this level.
(name (name . marker-or-number) (name . marker-or-number) ... )
One group of tags.
(name marker-or-number (name . marker-or-number) ... )
One Group of tags where the group has a starting position.
When you use speedbar-insert-generic-list
, there are some
variables you can set buffer-locally to change the behavior. The most
obvious is speedbar-tag-hierarchy-method
.
See Tag Hierarchy Methods.
This is the button type used for groups of tags, whether expanded
or added in via a hierarchy method. Two good values are
curly
and expandtag
. Curly is the default button, and
expandtag
is useful if the groups also has a position.
This is the button type used for a single tag.
Two good values are nil
and statictag
.
nil
is the default, and statictag
has the same width as
expandtag
.
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You may copy and distribute the Document in any medium, either commercially or noncommercially, provided that this License, the copyright notices, and the license notice saying this License applies to the Document are reproduced in all copies, and that you add no other conditions whatsoever to those of this License. You may not use technical measures to obstruct or control the reading or further copying of the copies you make or distribute. However, you may accept compensation in exchange for copies. If you distribute a large enough number of copies you must also follow the conditions in section 3.
You may also lend copies, under the same conditions stated above, and you may publicly display copies.
If you publish printed copies (or copies in media that commonly have 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.
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:
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.
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.”
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.
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.
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.
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.
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.
“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.
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.