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Pymacs #11, which-function-mode sluggish Dec 9, 2015
devel Remove redundant Feb 4, 2016
doc Doku updated Feb 10, 2016
extensions extensions/.nosearch added Apr 21, 2016
obsolete Rope bindings moved from pdee-bindings.el into pdee-init.el Dec 11, 2011
python-libs Starting to develop unittesting Nov 22, 2011
scripts Further editing on Apr 10, 2011
test #7, py-edit-docstring write content back Apr 26, 2016
.gitignore Remove redundant Feb 4, 2016
.travis.yml travis again Jul 1, 2015
CONTRIBUTORS Added Bastian to the CONTRIBUTORS list Jun 15, 2011
COPYING added license Jun 18, 2010
CREDITS py--create-new-shell sets py-exception-buffer incorrectly, lp:1456415 May 19, 2015
ChangeLog Updated readme and changelog with the new feature Jul 29, 2011
EXTENSIONS keep just one PDEE main directory Aug 15, 2012
INSTALL keep just one PDEE main directory Aug 15, 2012
INSTALL-INFO-FILES info-lookup-symbol, lp:1281950 Feb 19, 2014
IPYTHON keep just one PDEE main directory Aug 15, 2012
NEWS `py-split-window-on-execute-p' renamed `py-split-window-on-execute' Nov 8, 2014 added Nov 29, 2014 extended Jul 23, 2015 Remove redundant Feb 4, 2016
auto-complete-pycomplete.el keep just one PDEE main directory Aug 15, 2012
company-pycomplete.el keep just one PDEE main directory Aug 15, 2012
index.docbook keep just one PDEE main directory Aug 15, 2012
pdee-init.el wrong-coloring, lp:1315186 May 6, 2014
pdee-pkg.el Add package metadata files for ELPA packkage format and Marmalade add… Nov 26, 2011
pycomplete+.el keep just one PDEE main directory Aug 15, 2012 #11, which-function-mode sluggish Dec 9, 2015
pymacs.el Reduce compiler warnings Jul 5, 2015
python-components-auto-fill.el auto-fill fixed Jul 14, 2015
python-components-backward-forms.el Handle multiple decorators Sep 17, 2015
python-components-beginning-position-forms.el `py-hide-indent', `py-show-indent' Jan 4, 2016
python-components-booleans-beginning-forms.el `py-hide-indent', `py-show-indent' Jan 4, 2016
python-components-booleans-end-forms.el #1, select by indentation Dec 26, 2015
python-components-bounds-forms.el Some cleanup Jun 24, 2015
python-components-comment.el #1, `py-comment-indent', new command Dec 29, 2015
python-components-completion_flymake.el remove obsolete, risky forms Jun 29, 2013
python-components-copy-forms.el `py-hide-indent', `py-show-indent' Jan 4, 2016
python-components-copy.el Set `py-install-directory' if empty Jul 6, 2015
python-components-create-menu.el Menu updated Jul 1, 2015
python-components-dedicated-shells.el keep just one PDEE main directory Aug 15, 2012
python-components-delete-forms.el #1, select by indentation Dec 26, 2015
python-components-delete.el email updated Jul 1, 2015
python-components-electric.el `py-python-shell-mode', use current process Jul 11, 2015
python-components-end-forms.el Some cleanup Jun 24, 2015
python-components-end-position-forms.el #1, `py-comment-indent', new command Dec 29, 2015
python-components-exec-forms.el executes reconsidered Jul 8, 2015
python-components-execute-region.el Execute-region forms reconsidered Jul 7, 2015
python-components-execute.el lp:1579309, python buffer window on top when using python3 May 21, 2016
python-components-extensions.el Unused `py--match-paren-indented-empty' removed Jul 11, 2015
python-components-fast-forms.el `py-fast-process' fixed Nov 16, 2015
python-components-forms-code.el #1, select by indentation Dec 26, 2015
python-components-help.el #13, fill-paragraph with raw docstring Dec 22, 2015
python-components-hide-show.el `py-hide-indent', `py-show-indent' Jan 4, 2016
python-components-imenu.el email updated Jul 1, 2015
python-components-intern.el lp:1574731, wrong indent inside string Apr 25, 2016
python-components-kill-forms.el Menu docstrings minor-fix Jan 5, 2016
python-components-mark-forms.el #1, select by indentation Dec 26, 2015
python-components-menu.el Menu fixed Jul 9, 2015
python-components-misc-forms.el `py-beginning-of-for-block', lp:1367424 Jan 27, 2015
python-components-mode.el `py--edit-docstring-set-vars', proceed Apr 14, 2016
python-components-move.el lp:1545649, C-M-a and C-M-e stop at embedded defs. Feb 16, 2016
python-components-named-shells.el Revert "Revert "Named shell window-management, fixed"" Aug 20, 2015
python-components-narrow.el Set `py-install-directory' if empty Jul 6, 2015
python-components-paragraph.el #13, fill-paragraph with raw docstring Dec 22, 2015
python-components-pdb.el with-current-buffer vs. set-buffer issues Oct 2, 2015
python-components-re-forms.el Some cleanup Jun 24, 2015
python-components-section-forms.el email updated Jul 1, 2015
python-components-send.el Set `py-install-directory' if empty Jul 6, 2015
python-components-shell-complete.el `py-indent-or-complete' , lp:1508179 Oct 22, 2015
python-components-shell-menu.el email updated Jul 1, 2015
python-components-switches.el Reduce compiler warnings Jul 5, 2015
python-components-unified-completion.el keep just one PDEE main directory Aug 15, 2012
python-components-up-down.el #1, select by indentation Dec 26, 2015
python-components-versioned.el * beg-end.el: again Dec 10, 2015
python-dedicated-shells.el keep just one PDEE main directory Aug 15, 2012
python-edit-forms.el `py-beginning-of-for-block', lp:1367424 Jan 27, 2015
python-extended-executes.el #1, select by indentation Dec 26, 2015
python-mode-send.el keep just one PDEE main directory Aug 15, 2012
python-mode-utils.el keep just one PDEE main directory Aug 15, 2012
python-named-shells.el keep just one PDEE main directory Aug 15, 2012
python-shell-complete.el keep just one PDEE main directory Aug 15, 2012
python-shell-install-example-buffer.el #11, which-function-mode sluggish Dec 9, 2015
thing-at-point-utils.el keep just one PDEE main directory Aug 15, 2012
thingatpt-python-expressions.el keep just one PDEE main directory Aug 15, 2012
thingatpt-utils-base.el keep just one PDEE main directory Aug 15, 2012


Put the following into your initialization file:

(setq py-install-directory “PATH/TO/PYTHON-MODE/”) (add-to-list ‘load-path py-install-directory) (require ‘python-mode)

Selecting a Python shell:

Customize default Python shell as `py-shell-name’

`py-shell-name’ might be an installed default executable as shell command `type’ would display, but also a PATH/TO/EXECUTABLE

If different flavours of Python are installed, customize py-python-command - python2 py-python3-command py-ipython-command

py-python-command-args py-python3-command-args py-ipython-command-args

You might run code by another installed (I)Python-version than default.

Normally this would happen if a shebang in buffer specifies it. Shebang precedes default py-shell-name.

In case you will run code by default-shell, ignoring shebang, set `py-force-py-shell-name-p’ to. This might be done also via menu Python/…/Switches

Another way to enforce a different shell is specifiyng a path –interactively C-u prompts for that– or using commands which end in version like `py-execute-statement-python3’ See menu Python/Interpreter/Other/Ignoring Defaults

Invoking an (I)Python interactive shell

Commands related to a specific shell start with it’s name as `ipython-complete’. Open an installed shell by


This calls py-shell with its default arguments


if DEDICATED is set to `t’, shell will get an unique name.

Install a local shell by evaluating

(defun MY-LOCAL-SHELL () (interactive) (py-shell nil DEDICATED PATH-TO-LOCAL-SHELL))

Invoking versioned Python shells in interactive mode:

M-x py-shell RET ==> ”Python” M-x python RET ==> ”Python” M-x ipython RET ==> ”IPython” M-x python3 RET ==> ”Python3

When Path/To/Executable is given C-u python RET ==> ”PTE Python

Prefix conventions

Most python-mode.el commands start with prefix `py-’

`M-x py- TAB’ displays a list of them in completion-buffer. See also commands list delivered in directory doc.

List virtualenv related `M-x virtualenv- TAB’ resp. Pymacs commands `M-x pymacs-’

Execution code

Python code might be processed by an

  • interactive Python shell (DEFAULT)
  • non-interactive Python (`py-fast-process-p’) The latter, while design for large output, seems more reliable - see also

Both processes might run in

  • session, i.e. start from possible previous state (DEFAULT)
  • dedicated, (`py-dedicated-process-p’) run in separate process

There is also

  • python-mode-v5-behavior


Access is provided to a couple of known checkers like Flake8, pep8, pylint Need to be installed for example calling “pip install pep8” from a shell command-line Get flycheck from

Displaying Output

`py-execute-…’-commands arrive in buffer created by `py-shell’. It’s name is composed WRT to Python version used, it’s path etc.

Result of commands ending “-fast” arrives in `py-fast-output-buffer’

Window management

Variables in question:

** py-keep-windows-configuration

Default is nil. When non-nil, it takes precedence over `py-split-window-on-execute’ and `py-switch-buffers-on-execute-p’ settings

Useful, if a pre-designed set of python-shells/buffers should be maintained

** py-split-window-on-execute

When non-nil split windows according to value set.

Default is ‘just-two: when code is send to interpreter, split screen into source-code buffer and current py-shell result. Other buffers will be hidden that way.

When set to `t’, python-mode tries to reuse existing windows and will split only if needed.

With ‘always, results will displayed in a new window.

** py-switch-buffers-on-execute-p

Put focus into the output buffer: this will display buffer in any case


At the end of a word TAB by default calls completion.

Auto-completion should be available via

(require ‘auto-complete-config) (ac-config-default)

or for company:

(autoload ‘company-mode “company” nil t)

There is also a Pymacs based auto-completion mode see

Either use Pymacs and `company-mode’ with `pycomplete.el’ etc. –load stuff from folder completion–

or switch `py-auto-completion-mode-p’ - which relies on `py-shell-complete’, i.e. calls the current Python process.

Extern tools like jedi-server/mode should work too.


Beside common moves like `defun’, `statement’, block called via py-end-of-…, py-beginning-… specific Python-mode edits are delivered:

`py-expression’ and `py-partial-expression’.

Statement below is considered composed of two `py-expression’

a = [‘spam’, ‘eggs’, 100, 1234]


Assigment operator and all inside comments is ignored.

`py-partial-expression’ would match six sections

a = [‘spam’, ‘eggs’, 100, 1234]


When traversing code, `py-partial-expression’ climbs down and up all levels encountered, i.e. at opening `[’ `py-expression’ would return [‘spam’, ‘eggs’, 100, 1234], while one char behind at `” it yields `’spam’,’

  • py-sexp-function, When set, it’s value is called instead of `forward-sexp’, `backward-sexp Choices are py-partial-expression, py-expression, default nil


Customize boolean `py-set-fill-column-p’

If `t’, enables use Python specific `fill-column’ according to

`py-docstring-fill-column’, default is 72

and `py-comment-fill-column, default is 79

Comment- and docstring settings might be disabled by any non-integer value, which means: do not use a different value of `fill-column’ than emacs-wide

Python and IPython

Start IPython shell after loading python-mode via M-x ipython, not from plain shell.

Executing code through IPython should work as with regular Python, also getting completions from. However, with IPython, it feels a demi-second slower.


Start with Emacs -Q from the directory where python-mode.el lives. Open python-mode.el and evaluate it.

Open a file with ending “.py”.

M-x python RET

a regular Python-shell should appear

M-x IPython RET

an IPython-shell should be opened

** pdb doesn’t work at Windows Richard Stanton commented:

Running M-x pdb doesn’t work on my Windows machine, primarily because Windows (at least using the default shell) doesn’t automatically know what to do when you give it a .py command at the command line.

For example, here’s the suggested command when I run pdb on a file c:\projects/


If I accept this, I get an error “Spawning child process: Invalid argument”

A work-around to get it to work is to replace the suggested command with

c:\python27\python -i c:/python27/Lib/ c:/projects/

(note that I not only have to add the python command, but also fully qualify the script file, since otherwise it complains it can’t find the file).

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