My Emacs Python environment

Python mode¶

There are two Python modes: python-mode.el created by the Python community and python.el created by the Emacs community (David Love). The first version of python.el was included in Emacs 22 and an improved version was included in Emacs 23. I am currently using the default python.el included with Emacs 23. Below are some useful commands. For a complete list, open a Python file and run M-x apropos RET python RET

python-shift-left, C-c C-<

Decrease indentation of the region

python-shift-right, C-c C-<

Increase indentation of the region

python-switch-to-python, C-c C-z

Start (or switch) to a Python shell

python-send-buffer, C-c C-c

Run the current buffer in the Python interpreter

python-send-region, C-c C-r

Run the selected code in the Python interpreter

python-describe-symbol, C-c C-f

Get help on a Python symbol (Better than visiting the slow Python website, right?)

Configuration (~/.emacs changes)

(setq-default indent-tabs-mode nil)    ; use only spaces and no tabs
(setq default-tab-width 4)

Ropemacs¶

Ropemacs is an Emacs plugin to use Rope, a powerful Python refactoring library. It supports code completion, renaming, and other refactoring. Pymacs is a prerequisite for Ropemacs. Below are some useful commands. For more information, look in the Rope menu.

rope-code-assist, M-/

Code completion

rope-rename, C-c r r

Rename a variable, function, etc.

Installation

Note: pip install does not work with v0.25. Need to use `make install`

• Install Pymacs (Emacs part)

  $ curl -L https://github.com/pinard/Pymacs/tarball/v0.24-beta2 | tar zx
  $ cd pinard-Pymacs-016b0bc
  $ make 
  $ mkdir -p ~/.emacs.d/vendor/pymacs-0.24-beta2
  $ cp pymacs.el ~/.emacs.d/vendor/pymacs-0.24-beta2/pymacs.el 
  $ emacs -batch -eval '(byte-compile-file "~/.emacs.d/vendor/pymacs-0.24-beta2/pymacs.el")' 
  

• Install Pymacs (Python part)

  $ sudo pip install https://github.com/pinard/Pymacs/tarball/v0.24-beta2 
  

• Install Ropemacs and Rope

  $ sudo pip install http://bitbucket.org/agr/ropemacs/get/tip.tar.gz 
  

• Edit ~/.emacs to use Ropemacs

  (add-to-list 'load-path "~/.emacs.d/vendor/pymacs-0.24-beta2")
  (require 'pymacs)
  (pymacs-load "ropemacs" "rope-")
  (setq ropemacs-enable-autoimport t)

Auto Complete Mode¶

Auto Complete Mode is an extension to make Emacs auto-completion nicer. It creates a drowpdown in the middle of your text. It can use Ropemacs as a backend.

• Download, unpack and byte-compile

  $ cd ~/.emacs.d/vendor 
  $ curl http://cx4a.org/pub/auto-complete/auto-complete-1.2.tar.bz2 | tar jx 
  $ cd auto-complete-1.2 
  $ make byte-compile 
  

• Edit ~/.emacs

  (add-to-list 'load-path "~/.emacs.d/vendor/auto-complete-1.2")
  (require 'auto-complete-config)
  (add-to-list 'ac-dictionary-directories "~/.emacs.d/vendor/auto-complete-1.2/dict")
  (ac-config-default)

Yasnippet¶

YASnippet is a template system inspired by Textmate. Demo on YouTube

Code checking option 1: On-the-fly w/ Flymake¶

• Install PyFlakes and pep8

  $ sudo pip install pyflakes pep8
  

• Get flymake-cursor.el and save it as ~/.emacs.d/vendor/flymake-cursor.el.
• Edit ~/.emacs:

  (add-to-list 'load-path "~/.emacs.d/vendor")
  
  (add-hook 'find-file-hook 'flymake-find-file-hook)
  (when (load "flymake" t)
    (defun flymake-pyflakes-init ()
      (let* ((temp-file (flymake-init-create-temp-buffer-copy
                 'flymake-create-temp-inplace))
         (local-file (file-relative-name
              temp-file
              (file-name-directory buffer-file-name))))
        (list "pycheckers"  (list local-file))))
     (add-to-list 'flymake-allowed-file-name-masks
               '("\\.py\\'" flymake-pyflakes-init)))
  (load-library "flymake-cursor")
  (global-set-key [f10] 'flymake-goto-prev-error)
  (global-set-key [f11] 'flymake-goto-next-error)

• Create pycheckers, make it executable, and put it on your PATH

  #!/bin/bash
  
  pyflakes "$1"
  pep8 --ignore=E221,E701,E202 --repeat "$1"
  true

Code checking option 2: Manual checking w/ python-check¶

PyFlakes is a Lint-like tool for Python. It is like PyChecker, but it is fast. PyFlakes can be run from within Emacs using the default python mode in Emacs23.

• Install PyFlakes

  $ sudo pip install pyflakes
  

• Edit ~/.emacs

  (setq python-check-command "pyflakes")

• From Emacs, while visiting a Python file, run M-x python-check or C-c C-v or C-c C-w.

Django¶

Reference

• $ wget http://ourcomments.org/Emacs/DL/elisp/nxhtml/zip/nxhtml-2.08-100425.zip 
  $ unzip nxhtml-2.08-100425.zip
      
  

• (load "~/.emacs.d/nxhtml/autostart.el")
  (setq mumamo-background-colors nil) 
  (add-to-list 'auto-mode-alist '("\\.html$" . django-html-mumamo-mode))
      

References¶

• EnigmaCurry: Emacs as a powerful Python IDE (2008-03-09)
• EnigmaCurry: AutoComplete.el : Python Code Completion in Emacs (2009-01-21)
• Lei Chen: Setup Perfect Python Environment In Emacs (2009-01-30)
• Stack Overflow: Switching from python-mode.el to python.el (2008-12-12)
• Stack Overflow: python emacs completion(2009-04-15)
• Stack Overflow: How can I use Emacs Flymake mode for python with pyflakes and pylint checking code?
• Jesse D. Legg: Emacs for Python Programmers: Basics (2010-03-14)
• Jesse D. Legg: Emacs for Python Programmers #2: Virtualenv, IPython & Daemon Mode (2010-03-14)
• Pymacs installation documentation
• Edward O'Connor: ropemacs (2008-02-27)
• NIPY Documentation: Tricked out emacs for python coding
• Richard Riley: Emacs programming customisations
• Emacs Documentation: Flymake
• amix.dk: Static checking Python code

See also¶

• Emacs Python completion (library)
• CEDET (library)
• Doug Hellmann: Switching development contexts [in Emacs] with virtualenvwrapper
• Lacking Credibility: Mimicing source virtualenv/bin/activate in Emacs

15 Comments — Comments feed for this post

#!/usr/bin/env python

import re
import sys
from subprocess import *

p = Popen("pylint --rcfile=pylint.rc -f parseable -r n --disable=W0613,C,R %s" %
          sys.argv[1], shell = True, stdout = PIPE).stdout

for line in p.readlines():
    match = re.search("\\[([WE])(, (.+?))?\\]", line)
    if match:
        kind = match.group(1)
        func = match.group(3)

        if kind == "W":
            msg = "Warning"
        else:
            msg = "Error"

        if func:
            line = re.sub("\\[([WE])(, (.+?))?\\]",
                          "%s (%s):" % (msg, func), line)
        else:
            line = re.sub("\\[([WE])?\\]", "%s:" % msg, line)
    print line,
p.close()

p = Popen("pylint --rcfile=pylint.rc -f parseable -r n --disable-msg=W0613 --disable-msg-cat=C,R %s" %
      sys.argv[1], shell = True, stdout = PIPE).stdout

Post a comment