python-mode.el variables

====================

python-mode-modeline-display
----------------------------
String to display in Emacs modeline 

py-indent-offset
----------------
Amount of offset per level of indentation.
`M-x py-guess-indent-offset' can usually guess a good value when
you're editing someone else's Python code.

py-backslashed-lines-indent-offset
----------------------------------
Amount of offset per level of indentation of backslashed.
No semantic indent,  which diff to `py-indent-offset' indicates 

pdb-path
--------
Where to find pdb.py. Edit this according to your system.

If you ignore the location `M-x py-guess-pdb-path' might display it

py-verbose-p
------------
If indenting functions should report reached indent level.

Default is nil. 

py-store-result-p
-----------------
When non-nil, put resulting string of `py-execute-...' into kill-ring, so it might be yanked.

Default is nil

py-load-skeletons-p
-------------------
If skeleton definitions should be loaded, default is nil. 

py-load-pymacs-p
----------------
If Pymacs related stuff should be loaded.

Default is nil.

Pymacs has been written by François Pinard and many others.
See original source: http://pymacs.progiciels-bpi.ca

py-smart-operator-mode-p
------------------------
If python-mode calls (smart-operator-mode-on)

Default is non-nil. 

py-sexp-function
----------------
When set, it's value is called instead of `forward-sexp', `backward-sexp'

Default is nil. 

py-autopair-mode
----------------
If python-mode calls (autopair-mode-on)

Default is nil
Load `autopair-mode' written by Joao Tavora <joaotavora [at] gmail.com>
URL: http://autopair.googlecode.com 

py-no-completion-calls-dabbrev-expand-p
---------------------------------------
If completion function should call dabbrev-expand when no completion found. Default is `t'

See also `py-indent-no-completion-p'

py-indent-no-completion-p
-------------------------
If completion function should insert a TAB when no completion found. Default is `t'

See also `py-no-completion-calls-dabbrev-expand-p'

py-set-fill-column-p
--------------------
If python-mode should set fill-column

according values in `py-comment-fill-column' and `py-docstring-fill-column'.
Default is  nil

py-autofill-timer-delay
-----------------------
Delay when idle before functions ajusting  `py-docstring-fill-column' resp. `py-comment-fill-column' are called. 

py-docstring-fill-column
------------------------
Value of `fill-column' to use when filling a docstring.
Any non-integer value means do not use a different value of
`fill-column' when filling docstrings.

py-comment-fill-column
----------------------
Value of `fill-column' to use when filling a comment.
Any non-integer value means do not use a different value of
`fill-column' when filling docstrings.

py-fontify-shell-buffer-p
-------------------------
If code in Python shell should be highlighted as in script buffer.

Default is nil.

If `t', related vars like `comment-start' will be set too.
Seems convenient when playing with stuff in IPython shell
Might not be TRT when a lot of output arrives 

py-modeline-display-full-path-p
-------------------------------
If the full PATH/TO/PYTHON should be displayed in shell modeline.

Default is nil. Note: when `py-shell-name' is specified with path, it's shown as an acronym in buffer-name already. 

py-modeline-acronym-display-home-p
----------------------------------
If the modeline acronym should contain chars indicating the home-directory.

Default is nil 

py-install-directory
--------------------
Directory where python-mode.el and it's subdirectories should be installed. Needed for completion and other environment stuff only. 

py-guess-py-install-directory-p
-------------------------------
If in cases, `py-install-directory' isn't set,  `py-set-load-path'should guess it from `buffer-file-name'. 

py-extensions
-------------
File where extensions to python-mode.el should be installed. Used by virtualenv support. 

py-pylint-offer-current-p
-------------------------
If current buffers file should be offered for check.

Default is non-nil. If nil, `py-pylint-run' offers filename from history 

py-hide-show-minor-mode-p
-------------------------
If hide-show minor-mode should be on, default is nil. 

empty-comment-line-separates-paragraph-p
----------------------------------------
Consider paragraph start/end lines with nothing inside but comment sign.

Default is  non-nil

py-if-name-main-permission-p
----------------------------
Allow execution of code inside blocks started
by "if __name__== '__main__':".

Default is non-nil

py-use-font-lock-doc-face-p
---------------------------
If documention string inside of def or class get `font-lock-doc-face'.

`font-lock-doc-face' inherits `font-lock-string-face'.
Call M-x `customize-face' in order to have a visible effect. 

py-defun-use-top-level-p
------------------------
When non-nil, keys C-M-a, C-M-e address top-level form.

Default is nil.

Beginning- end-of-defun forms use
commands `py-beginning-of-top-level', `py-end-of-top-level'

mark-defun marks top-level form at point etc.


py-tab-shifts-region-p
----------------------
If `t', TAB will indent/cycle the region, not just the current line.

Default is  nil

py-tab-indents-region-p
-----------------------
When `t' and first TAB doesn't shift, indent-region is called.

Default is  nil

py-block-comment-prefix-p
-------------------------
If py-comment inserts py-block-comment-prefix.

Default is t

py-org-cycle-p
--------------
When non-nil, command `org-cycle' is available at shift-TAB, <backtab>

Default is nil. 

ipython-complete-use-separate-shell-p
-------------------------------------
If `ipython-complete' should use a separate shell. Thus prompt-counter is not incremented by completion. 

py-outline-minor-mode-p
-----------------------
If outline minor-mode should be on, default is `t'. 

py-outline-mode-keywords
------------------------
Keywords composing visible heads. 

py-start-run-py-shell
---------------------
If `python-mode' should start a python-shell, `py-shell'.

Default is `nil'. 

py-start-run-ipython-shell
--------------------------
If `python-mode' should start an ipython-shell.

Default is `nil'. 

py-close-provides-newline
-------------------------
If a newline is inserted, when line after block isn't empty. Default is non-nil. 

py-dedent-keep-relative-column
------------------------------
If point should follow dedent or kind of electric move to end of line. Default is t - keep relative position. 

py-indent-honors-multiline-listing
----------------------------------
If `t', indents to 1+ column of opening delimiter. If `nil', indent adds one level to the beginning of statement. Default is `nil'. 

py-indent-paren-spanned-multilines-p
------------------------------------
If non-nil, indents elements of list a value of `py-indent-offset' to first element:

def foo():
    if (foo &&
            baz):
        bar()

Default lines up with first element:

def foo():
    if (foo &&
        baz):
        bar()


py-indent-honors-inline-comment
-------------------------------
If non-nil, indents to column of inlined comment start.
Default is nil. 

py-closing-list-dedents-bos
---------------------------
When non-nil, indent list's closing delimiter like start-column.

It will be lined up under the first character of
 the line that starts the multi-line construct, as in:

my_list = [
    1, 2, 3,
    4, 5, 6,
]

result = some_function_that_takes_arguments(
    'a', 'b', 'c',
    'd', 'e', 'f',
)

Default is nil, i.e.

my_list = [
    1, 2, 3,
    4, 5, 6,
    ]
result = some_function_that_takes_arguments(
    'a', 'b', 'c',
    'd', 'e', 'f',
    )

Examples from PEP8


py-closing-list-space
---------------------
Number of chars, closing parenthesis outdent from opening, default is 1 

py-closing-list-keeps-space
---------------------------
If non-nil, closing parenthesis dedents onto column of opening plus `py-closing-list-space', default is nil 

py-electric-kill-backward-p
---------------------------
Affects `py-electric-backspace'. Default is nil.

If behind a delimited form of braces, brackets or parentheses,
backspace will kill it's contents

With when cursor after
my_string[0:1]
--------------^

==>

my_string[]
----------^

In result cursor is insided emptied delimited form.

py-electric-colon-active-p
--------------------------
`py-electric-colon' feature.  Default is `nil'. See lp:837065 for discussions.

See also `py-electric-colon-bobl-only' 

py-electric-colon-bobl-only
---------------------------
When inserting a colon, do not indent lines unless at beginning of block

See lp:1207405 resp. `py-electric-colon-active-p' 

py-electric-colon-greedy-p
--------------------------
If py-electric-colon should indent to the outmost reasonable level.

If nil, default, it will not move from at any reasonable level. 

py-electric-colon-newline-and-indent-p
--------------------------------------
If non-nil, `py-electric-colon' will call `newline-and-indent'.  Default is `nil'. 

py-electric-comment-p
---------------------
If "#" should call `py-electric-comment'. Default is `nil'. 

py-electric-comment-add-space-p
-------------------------------
If py-electric-comment should add a space.  Default is `nil'. 

py-mark-decorators
------------------
If py-mark-def-or-class functions should mark decorators too. Default is `nil'. 

py-tab-indent
-------------
Non-nil means TAB in Python mode calls `py-indent-line'.

py-return-key
-------------
Which command <return> should call. 

py-complete-function
--------------------
When set, enforces function todo completion, default is nil.

Normally python-mode, resp. inferior-python-mode know best which function to use. 

ipython-complete-function
-------------------------
Function used for completion in IPython shell buffers. 

py-encoding-string
------------------
Default string specifying encoding of a Python file. 

py-shebang-startstring
----------------------
Detecting the shell in head of file. 

py-python-command-args
----------------------
List of string arguments to be used when starting a Python shell.

py-jython-command-args
----------------------
List of string arguments to be used when starting a Jython shell.

py-cleanup-temporary
--------------------
If temporary buffers and files used by functions executing region should be deleted afterwards. 

py-execute-no-temp-p
--------------------
Seems Emacs-24.3 provided a way executing stuff without temporary files. 

py-lhs-inbound-indent
---------------------
When line starts a multiline-assignment: How many colums indent should be more than opening bracket, brace or parenthesis. 

py-continuation-offset
----------------------
Additional amount of offset to give for some continuation lines.
Continuation lines are those that immediately follow a backslash
terminated line. 

py-indent-tabs-mode
-------------------
Python-mode starts `indent-tabs-mode' with the value specified here, default is nil. 

py-smart-indentation
--------------------
Should `python-mode' try to automagically set some indentation variables?
When this variable is non-nil, two things happen when a buffer is set
to `python-mode':

    1. `py-indent-offset' is guessed from existing code in the buffer.
       Only guessed values between 2 and 8 are considered.  If a valid
       guess can't be made (perhaps because you are visiting a new
       file), then the value in `py-indent-offset' is used.

    2. `indent-tabs-mode' is turned off if `py-indent-offset' does not
       equal `tab-width' (`indent-tabs-mode' is never turned on by
       Python mode).  This means that for newly written code, tabs are
       only inserted in indentation if one tab is one indentation
       level, otherwise only spaces are used.

Note that both these settings occur *after* `python-mode-hook' is run,
so if you want to defeat the automagic configuration, you must also
set `py-smart-indentation' to nil in your `python-mode-hook'.

py-block-comment-prefix
-----------------------
String used by M-x comment-region to comment out a block of code.
This should follow the convention for non-indenting comment lines so
that the indentation commands won't get confused (i.e., the string
should be of the form `#x...' where `x' is not a blank or a tab, and
`...' is arbitrary).  However, this string should not end in whitespace.

py-indent-comments
------------------
When t, comment lines are indented. 

py-uncomment-indents-p
----------------------
When non-nil, after uncomment indent lines. 

py-separator-char
-----------------
Values set by defcustom only will not be seen in batch-mode. 

py-custom-temp-directory
------------------------
If set, will take precedence over guessed values from `py-temp-directory'. Default is the empty string.

When set, make sure the directory exists. 

py-beep-if-tab-change
---------------------
Ring the bell if `tab-width' is changed.
If a comment of the form

  	# vi:set tabsize=<number>:

is found before the first code line when the file is entered, and the
current value of (the general Emacs variable) `tab-width' does not
equal <number>, `tab-width' is set to <number>, a message saying so is
displayed in the echo area, and if `py-beep-if-tab-change' is non-nil
the Emacs bell is also rung as a warning.

py-jump-on-exception
--------------------
Jump to innermost exception frame in *Python Output* buffer.
When this variable is non-nil and an exception occurs when running
Python code synchronously in a subprocess, jump immediately to the
source code of the innermost traceback frame.

py-ask-about-save
-----------------
If not nil, ask about which buffers to save before executing some code.
Otherwise, all modified buffers are saved without asking.

py-backspace-function
---------------------
Function called by `py-electric-backspace' when deleting backwards.

py-delete-function
------------------
Function called by `py-electric-delete' when deleting forwards.

py-pdbtrack-do-tracking-p
-------------------------
Controls whether the pdbtrack feature is enabled or not.
When non-nil, pdbtrack is enabled in all comint-based buffers,
e.g. shell buffers and the *Python* buffer.  When using pdb to debug a
Python program, pdbtrack notices the pdb prompt and displays the
source file and line that the program is stopped at, much the same way
as gud-mode does for debugging C programs with gdb.

py-pdbtrack-filename-mapping
----------------------------
Supports mapping file paths when opening file buffers in pdbtrack.
When non-nil this is an alist mapping paths in the Python interpreter
to paths in Emacs.

py-pdbtrack-minor-mode-string
-----------------------------
String to use in the minor mode list when pdbtrack is enabled.

py-import-check-point-max
-------------------------
Maximum number of characters to search for a Java-ish import statement.
When `python-mode' tries to calculate the shell to use (either a
CPython or a Jython shell), it looks at the so-called `shebang' line
-- i.e. #! line.  If that's not available, it looks at some of the
file heading imports to see if they look Java-like.

py-jython-packages
------------------
Imported packages that imply `jython-mode'.

py-current-defun-show
---------------------
If `py-current-defun' should jump to the definition, highlight it while waiting PY-WHICH-FUNC-DELAY seconds, before returning to previous position.

Default is `t'.

py-current-defun-delay
----------------------
When called interactively, `py-current-defun' should wait PY-WHICH-FUNC-DELAY seconds at the definition name found, before returning to previous position. 

py-send-receive-delay
---------------------
Seconds to wait for output, used by `py-send-receive'. 

py-honor-IPYTHONDIR-p
---------------------
When non-nil ipython-history file is constructed by $IPYTHONDIR
followed by "/history". Default is nil.

Otherwise value of py-ipython-history is used. 

py-ipython-history
------------------
ipython-history default file. Used when py-honor-IPYTHONDIR-p is nil (default) 

py-honor-PYTHONHISTORY-p
------------------------
When non-nil python-history file is set by $PYTHONHISTORY
Default is nil.

Otherwise value of py-python-history is used. 

py-python-history
-----------------
python-history default file. Used when py-honor-PYTHONHISTORY-p is nil (default) 

py-master-file
--------------
If non-nil, M-x py-execute-buffer executes the named
master file instead of the buffer's file.  If the file name has a
relative path, the value of variable `default-directory' for the
buffer is prepended to come up with a file name.

Beside you may set this variable in the file's local
variable section, e.g.:

    # Local Variables:
    # py-master-file: "master.py"
    # End:



py-pychecker-command
--------------------
Shell command used to run Pychecker.

py-pychecker-command-args
-------------------------
List of string arguments to be passed to pychecker.

py-pep8-command
---------------
Shell command used to run pep8.

py-pep8-command-args
--------------------
List of string arguments to be passed to pylint.

Default is "" 

py-pyflakespep8-command
-----------------------
Shell command used to run `pyflakespep8'.

py-pyflakespep8-command-args
----------------------------
List of string arguments to be passed to pyflakespep8.

Default is "" 

py-pyflakes-command
-------------------
Shell command used to run Pyflakes.

py-pyflakes-command-args
------------------------
List of string arguments to be passed to pyflakes.

Default is "" 

py-pylint-command
-----------------
Shell command used to run Pylint.

py-pylint-command-args
----------------------
List of string arguments to be passed to pylint.

Default is "--errors-only" 

py-shell-input-prompt-1-regexp
------------------------------
A regular expression to match the input prompt of the shell.

py-shell-input-prompt-2-regexp
------------------------------
A regular expression to match the input prompt of the shell after the
  first line of input.

py-shell-prompt-read-only
-------------------------
If non-nil, the python prompt is read only.  Setting this
variable will only effect new shells.

py-fileless-buffer-use-default-directory-p
------------------------------------------
When `py-use-current-dir-when-execute-p' is non-nil and no buffer-file exists, value of `default-directory' sets current working directory of Python output shell

py-keep-shell-dir-when-execute-p
--------------------------------
Don't change Python shell's current working directory when sending code.

See also `py-execute-directory'

py-switch-buffers-on-execute-p
------------------------------
When non-nil switch to the Python output buffer. 

py-split-windows-on-execute-p
-----------------------------
When non-nil split windows. 

py-max-split-windows
--------------------
When split windows is enabled the maximum windows to allow
  before reusing other windows.

py-split-windows-on-execute-function
------------------------------------
How window should get splitted to display results of py-execute-... functions. 

py-hide-show-keywords
---------------------
Keywords composing visible heads.
Also used by (minor-)outline-mode 

py-hide-show-hide-docstrings
----------------------------
Controls if doc strings can be hidden by hide-show

py-paragraph-fill-docstring-p
-----------------------------
If `py-fill-paragraph', when inside a docstring, should fill the complete string.

Default is nil.

Convenient use of `M-q' inside docstrings
See also `py-docstring-style'


python-mode-hook
----------------
Hook run after entering python-mode-modeline-display mode.
No problems result if this variable is not bound.
`add-hook' automatically binds it.  (This is true for all hook variables.)

py-imenu-create-index-p
-----------------------
Non-nil means Python mode creates and displays an index menu of functions and global variables. 

py-imenu-create-index-function
------------------------------
Switch between `py-imenu-create-index-new', which also lists modules variables,  and series 5. index-machine

py-shell-name
-------------
A PATH/TO/EXECUTABLE or default value `py-shell' may look for, if no shell is specified by command. 

py-shell-toggle-1
-----------------
A PATH/TO/EXECUTABLE or default value used by `py-toggle-shell'. 

py-shell-toggle-2
-----------------
A PATH/TO/EXECUTABLE or default value used by `py-toggle-shell'. 

py-match-paren-mode
-------------------
Non-nil means, cursor will jump to beginning or end of a block.
This vice versa, to beginning first.
Sets `py-match-paren-key' in python-mode-map.
Customize `py-match-paren-key' which key to use. 

py-match-paren-key
------------------
String used by M-x comment-region to comment out a block of code.
This should follow the convention for non-indenting comment lines so
that the indentation commands won't get confused (i.e., the string
should be of the form `#x...' where `x' is not a blank or a tab, and
`...' is arbitrary).  However, this string should not end in whitespace.

py-kill-empty-line
------------------
If t, py-indent-forward-line kills empty lines. 

py-remove-cwd-from-path
-----------------------
Whether to allow loading of Python modules from the current directory.
If this is non-nil, Emacs removes '' from sys.path when starting
an inferior Python process.  This is the default, for security
reasons, as it is easy for the Python process to be started
without the user's realization (e.g. to perform completion).

py-imenu-show-method-args-p
---------------------------
Controls echoing of arguments of functions & methods in the Imenu buffer.
When non-nil, arguments are printed.

py-history-filter-regexp
------------------------
Input matching this regexp is not saved on the history list.
Default ignores all inputs of 0, 1, or 2 non-blank characters.

inferior-python-filter-regexp
-----------------------------
Input matching this regexp is not saved on the history list.
Default ignores all inputs of 0, 1, or 2 non-blank characters.

py-set-complete-keymap-p
------------------------
If `py-complete-initialize', which sets up enviroment for Pymacs based py-complete, should load it's keys into `python-mode-map'

Default is nil.
See also resp. edit `py-complete-set-keymap' 

py-use-local-default
--------------------
If `t', py-shell will use `py-shell-local-path' instead
  of default Python.

Making switch between several virtualenv's easier,
 `python-mode' should deliver an installer, so named-shells pointing to virtualenv's will be available. 

py-highlight-error-source-p
---------------------------
When py-execute-... commands raise an error, respective code in source-buffer will be highlighted. Default is nil.

M-x `py-remove-overlays-at-point' removes that highlighting.
 

py-set-pager-cat-p
------------------
If the shell environment variable $PAGER should set to `cat'.

If `t', use `C-c C-r' to jump to beginning of output. Then scroll normally.

Avoids lp:783828, "Terminal not fully functional", for help('COMMAND') in python-shell

When non-nil, imports module `os' 

py-prompt-on-changed-p
----------------------
When called interactively, ask for save before a changed buffer is sent to interpreter.

Default is `t'

py-dedicated-process-p
----------------------
If commands executing code use a dedicated shell.

Default is nil

py-shell-local-path
-------------------
If `py-use-local-default' is non-nil, `py-shell' will use EXECUTABLE indicated here incl. path. 

py-edit-only-p
--------------
When `t' `python-mode' will not take resort nor check for installed Python executables. Default is nil.

See bug report at launchpad, lp:944093. 

py-force-py-shell-name-p
------------------------
When `t', execution with kind of Python specified in `py-shell-name' is enforced, possibly shebang doesn't take precedence. 

python-mode-v5-behavior-p
-------------------------
Execute region through `shell-command-on-region' as
v5 did it - lp:990079. This might fail with certain chars - see UnicodeEncodeError lp:550661

py-trailing-whitespace-smart-delete-p
-------------------------------------
Default is nil. When t, python-mode calls
    (add-hook 'before-save-hook 'delete-trailing-whitespace nil 'local)

Also commands may delete trailing whitespace by the way.
When editing other peoples code, this may produce a larger diff than expected 

py-newline-delete-trailing-whitespace-p
---------------------------------------
Delete trailing whitespace maybe left by `py-newline-and-indent'.

Default is `t'. See lp:1100892 

py-warn-tmp-files-left-p
------------------------
Messages a warning, when `py-temp-directory' contains files susceptible being left by previous Python-mode sessions. See also lp:987534 

py-ipython-execute-delay
------------------------
Delay needed by execute functions when no IPython shell is running. 

python-shell-buffer-name
------------------------
Default buffer name for Python interpreter.

python-shell-interpreter
------------------------
Default Python interpreter for shell.

python-shell-prompt-regexp
--------------------------
Regular Expression matching top-level input prompt of python shell.
It should not contain a caret (^) at the beginning.

py-ffap-p
---------
Select python-modes way to find file at point.

Default is nil 

python-ffap-setup-code
----------------------
Python code to get a module path.

py-ffap-string-code
-------------------
Python code used to get a string with the path of a module.

py-eldoc-setup-code
-------------------
Python code to setup documentation retrieval.

py-setup-codes
--------------
List of code run by `py-shell-send-setup-codes'.

py-shell-prompt-regexp
----------------------
Regular Expression matching top-level input prompt of python shell.
It should not contain a caret (^) at the beginning.

python-shell-completion-setup-code
----------------------------------
Code used to setup completion in inferior Python processes.

python-shell-module-completion-string-code
------------------------------------------
Python code used to get completions separated by semicolons for imports.

For IPython v0.11, add the following line to
`python-shell-completion-setup-code':

from IPython.core.completerlib import module_completion

and use the following as the value of this variable:

';'.join(module_completion('''%s'''))

strip-chars-before
------------------
Regexp indicating which chars shall be stripped before STRING - which is defined by `string-chars-preserve'.

strip-chars-after
-----------------
Regexp indicating which chars shall be stripped after STRING - which is defined by `string-chars-preserve'.

py-docstring-style
------------------
Implemented styles are DJANGO, ONETWO, PEP-257, PEP-257-NN,
SYMMETRIC, and NIL.

A value of NIL won't care about quotes
position and will treat docstrings a normal string, any other
value may result in one of the following docstring styles:

DJANGO:

    """
    Process foo, return bar.
    """

    """
    Process foo, return bar.

    If processing fails throw ProcessingError.
    """

ONETWO:

    """Process foo, return bar."""

    """
    Process foo, return bar.

    If processing fails throw ProcessingError.

    """

PEP-257:

    """Process foo, return bar."""

    """Process foo, return bar.

    If processing fails throw ProcessingError.

    """

PEP-257-NN:

    """Process foo, return bar."""

    """Process foo, return bar.

    If processing fails throw ProcessingError.
    """

SYMMETRIC:

    """Process foo, return bar."""

    """
    Process foo, return bar.

    If processing fails throw ProcessingError.
    """

py-execute-directory
--------------------
When set, stores the file's default directory-name py-execute-... functions act upon.

Used by Python-shell for output of `py-execute-buffer' and related commands. See also `py-use-current-dir-when-execute-p'

py-use-current-dir-when-execute-p
---------------------------------
When `t', current directory is used by Python-shell for output of `py-execute-buffer' and related commands.

See also `py-execute-directory'

py-shell-prompt-output-regexp
-----------------------------
Regular Expression matching output prompt of python shell.
It should not contain a caret (^) at the beginning.

py-output-buffer
----------------
When `py-enforce-output-buffer-p' is non-nil, provides the
default for output-buffer. 

py-enforce-output-buffer-p
--------------------------
When non-nil, current value of `py-output-buffer' is used for output,
regardless of environment. Default is nil

py-underscore-word-syntax-p
---------------------------
If underscore chars should be of syntax-class `word', not of `symbol'.

Underscores in word-class makes `forward-word' etc. travel the indentifiers. Default is `t'.

See bug report at launchpad, lp:940812