Emacs

Emacs (the major flavors being GnuEmacs and XEmacs) is a text editor which come with good support for writing Python code. Each has its strengths and weaknesses, but in general either provide very nice environments for the Python programmer.

Tools for Python coders

For stupid historical reasons, GnuEmacs and XEmacs come with different major mode for editing Python code, though both do a fine job of it. Please get involved if you want to help.

Some tools have been written for using Python from Emacs:

• EmacsPythonMode, a major mode for programming Python in Emacs.

  • Rudimentary completion is implemented on top of EmacsPythonMode by EmacsPythonCompletion

• python.el, a Python mode which will be included when Emacs 22 is released, with a number of advantages over python-mode.el. For a version with fixes and enhancements (as of 2006-06) and one that works with Emacs 21, see http://www.loveshack.ukfsn.org/emacs.

• Emacs GUD PDB, support for sourcelevel debugging of Python code in Emacs. (Note: thanx to Ganesan R: Create the following script with the file name as "pdb" in your path so emacs can find pdb and default to filename arguments in the current dirctory: exec python /usr/lib/python2.3/pdb.py "$@")

• Pymacs(download), an extension for allowing Emacs users to extend Emacs using Python, where they might have traditionally used Emacs LISP. ' There are also PyMacs notes on the Emacs wiki.

• Emacs Language Sensitive Editor (ELSE), an template-based minor mode for Emacs, with templates for Python.

• OO-Browser, an Emacs class browser for object-oriented languages with support for Python.

• The emacspeak audio desktop is a speech interface that allows visually impaired users to interact independently and efficiently with the computer. It has editing support for interactive Python development. Features aural highlighting, structured browsing and debugging.

Support for C Python core developers

Both Emacs and XEmacs have support for developers hacking on the Python C code itself. If you're developing Python 2.x, just use the standard python style that comes with c-mode. If you're hacking on Python 3.x, you'll want to add the following code to your .emacs file (given by Georg Brandl):

(c-add-style
  "python-new"
  '((indent-tabs-mode . nil)
    (fill-column      . 78)
    (c-basic-offset   . 4)
    (c-offsets-alist  . ((substatement-open . 0)
                         (inextern-lang . 0)
                         (arglist-intro . +)
                         (knr-argdecl-intro . +)))
    (c-hanging-braces-alist . ((brace-list-open)
                               (brace-list-intro)
                               (brace-list-close)
                               (brace-entry-open)
                               (substatement-open after)
                               (block-close . c-snug-do-while)))
    (c-block-comment-prefix . "* "))
  )

;; This is a very crude hook that auto-selects the C style depending on
;; whether it finds a line starting with tab in the first 3000 characters
;; in the file
(defun c-select-style ()
   (save-excursion
     (if (re-search-forward "^\t" 3000 t)
         (c-set-style "python")
       (c-set-style "python-new"))))
(add-hook 'c-mode-hook 'c-select-style)

Note: We should try to get the style into upstream c-mode.

Other resources

• The Emacs Wiki, a good starting place.

• GnuEmacs web page.

• XEmacs web page.

CategoryEditors