path: root/docs/user/emacs.txt

.. -*- coding: utf-8 -*-

========================================
   Emacs Support for reStructuredText
========================================

:Author: Martin Blais <blais@furius.ca>
:Date: 2007-12-03
:Abstract:

    High-level description of the existing emacs support for editing
    reStructuredText text documents.  Suggested setup code and usage
    instructions are provided.

.. contents::
..
    1   Introduction
    2   Installation
    3   Section Decorations
      3.1  Adjusting a Section Title
      3.2  Promoting and Demoting Many Sections
      3.3  Redoing All the Decorations to Your Taste
      3.4  Customizations for Decorations
      3.5  Viewing the Hierarchy of Section Decorations
    4   Section Movement and Selection
    5   Operating on Blocks of Text
      5.1  Shifting Text Horizontally Intelligently
      5.2  Bulleting and Enumerating Lists
        5.2.1  Straightening Existing Bullet List Hierarchies
      5.3  Creating and Removing Line Blocks
      5.4  Commenting a Region of Text
    6   Converting Documents from Emacs
    7   Table-of-Contents Features
      7.1  Inserting a Table of Contents
      7.2  Maintaining the Table of Contents Up-to-date
    8   Syntax Highlighting via Font-Lock
      8.1  Face Customization
        8.1.1  Default Fonts
    9   Other Useful Settings
      9.1  ``text-mode`` Settings
      9.2  Editing Tables: Emacs table mode
      9.3  Character Processing
    10  Credits
      10.1  Obsolete Files
    11  Future Work


Introduction
============

reStructuredText_ is a series of conventions that allows a
toolset--docutils--to extract generic document structure from simple
text files. For people who use Emacs_, there is a package that adds a
major mode that supports editing in the conventions of
reStructuredText_: ``rst.el``. This document describes the features it
provides, and how to setup your emacs to use them and how to invoke
them.


Installation
============

The emacs support is implemented as an Emacs major mode (``rst-mode``)
provided by the ``rst.el`` emacs package. In order to use
``rst-mode``, you need to put the ``rst.el`` in a directory located in
your emacs ``load-path``, and to load it with::

  (require 'rst)

To enable ``rst-mode``, simple type ``M-x rst-mode``. Alternatively,
you can modify ``auto-mode-alist`` to automatically turn it on
whenever you visit reStructuredText_ documents::

   (setq auto-mode-alist
         (append '(("\\.txt$" . rst-mode)
                   ("\\.rst$" . rst-mode)
                   ("\\.rest$" . rst-mode)) auto-mode-alist))

If have local variables enabled (see ``enable-local-variables`` in the
Emacs manual), you can also add the following at the top of your
documents to trigger rst-mode::

   .. -*- mode: rst -*-

Or this at the end of your documents::

   ..
      Local Variables:
      mode: rst
      End:

``rst-mode`` automatically binds several keys for invoking special
handy functions for editing ReStructuredText. As is the custom for
Emacs major modes, most keys are bound to ``C-c C-LETTER``.

If you insert an inline table-of-contents at the top of the document,
you may want to add a hook to automatically update it everytime you
adjust a section title::

  (add-hook 'rst-adjust-hook 'rst-toc-update)

Additional configuration variables can be customized and can be found
by browsing the source code for ``rst.el``.


Section Decorations
===================

The rst package does not completely parse all the reStructuredText_
constructs, but it contains the ability to recognize the section
decorations and to build the hierarchy of the document. What we call
section decorations or adornments are the underlines or under- and
overlines used to mark a section title.

Adjusting a Section Title
-------------------------

There is a function that helps a great deal to maintain these
decorations: ``rst-adjust`` (bound to ``C-c C-a``, or ``C-=`` by
default). This function is a Swiss army knife that can be invoked
repeatedly and whose behaviour depends on context:

#. If there is an incomplete underline, e.g.::

      My Section Title
      ^^

   Invocation will complete the section title.  You can simply enter a
   few characters of the title and invoke the function to complete it.
   It can also be used to adjust the length of the existing decoration
   when you need to edit the title.

#. If there is no section decoration, a decoration one level under the
   last encountered section level is added;

#. If there is already a section decoration, it is promoted to the
   next level.  You can invoke it like this repeatedly to cycle the
   title through the hierarchy of existing decorations.

Invoking the function with a negative prefix argument, e.g. ``C--
C-=``, will effectively reverse the direction of decoration cycling.
To alternate between underline-only and over-and-under styles, you can
use a regular prefix argument, e.g. ``C-u C-=``.  See the
documentation of ``rst-adjust`` for more description of the prefix
arguments to alter the behaviour of the function.

Promoting and Demoting Many Sections
------------------------------------

When you are re-organizing the structure of a document, it can be
useful to change the level of a number of section titles.  The same
key binding can be used to do that: if the region is active when the
binding is invoked, all the section titles that are within the region
are promoted accordingly (or demoted, with negative prefix arg).

Redoing All the Decorations to Your Taste
-----------------------------------------

If you open someone else's file and the decorations it contains are
unfamiliar, you may want to readjust them to fit your own preferred
hierarchy of decorations. This can be difficult to perform by hand.
However, you can do this easily by invoking
``rst-straighten-decorations`` (``C-c C-s``), which operates on the
entire buffer.

Customizations for Decorations
------------------------------

You can set the variable ``rst-preferred-decorations`` to a list of
the decorations that you like to use for documents.  Everyone has
their preference.  ``rst-default-indent`` can be set to the number of
indent spaces preferred for the over-and-under decoration style.

Viewing the Hierarchy of Section Decorations
--------------------------------------------

You can visualize the hierarchy of the section decorations in the
current buffer by invoking ``rst-display-decorations-hierarchy``,
bound on ``C-c C-h``.  A temporary buffer will appear with fake
section titles rendered in the style of the current document.  This
can be useful when editing other people's documents to find out which
section decorations correspond to which levels.


Section Movement and Selection
==============================

You can move the cursor between the different section titles by using
the ``rst-backward-section`` and ``rst-forward-section`` functions, by
default bound to the ``C-c C-p`` and ``C-c C-n`` keys.

To mark the section that cursor lies in, use ``rst-mark-section``
(``C-c C-m``).



Operating on Blocks of Text
===========================

Shifting Text Horizontally Intelligently
----------------------------------------

Due to the nature of reStructuredText_, lists are indented by two or
three characters, e.g. bulleted lists use two chars::

   - Fruits

     - Bananas
     - Apples
     - Oranges

   - Veggies

     - Zucchini
     - Chick Peas

while enumerated lists are indented by 3 or more characters ::

   9. Apples

      Oranges are tasty.

   10. Oranges

       Oranges are zesty.

To this effect, when shifting text, it can be useful to have functions
which understand which indent to use by using the context around the
region. Those functions are ``rst-shift-region-right`` and
``rst-shift-region-left``.

You can use ``C-c C-r`` and ``C-c C-l`` to shift the active region.
These bindings are similar to the ones provided by python-mode for
editing python code and behave similarly.  They automatically inspect
the lines of text before the currently selected region to determine
what the appropriate column positions are.


Bulleting and Enumerating Lists
-------------------------------

Sometimes it can be useful to insert bullet list markers enumeration
number before a number of lines or paragraphs.  You can do this easily
by invoking ``rst-enumerate-region`` (``C-c C-e``), for example, the
following::

  Apples

  Oranges

  Bananas

becomes::

  1. Apples

  2. Oranges

  3. Bananas

``rst-listify-region`` (``C-c C-b``) does the same, but only adds
bullet list markers, e.g.::

  Apples

  Oranges

  Bananas

becomes::

  - Apples

  - Oranges

  - Bananas


By default, each paragraph starting on the leftmost line in the
highlighted region will be taken to be a single list or enumeration
item, for example, enumerating the following::

   An apple a day
   keeps the doctor away.

   But oranges
   are tastier than apples.

   If you preferred bananas
   you may be
   a monkey.

Will result in::

   1. An apple a day
      keeps the doctor away.

   2. But oranges
      are tastier than apples.

   3. If you preferred bananas
      you may be
      a monkey.

If you would like to enumerate each of the lines, use a prefix
argument on the preceding commands, e.g.::

  Apples
  Oranges
  Bananas

becomes::

  - Apples
  - Oranges
  - Bananas

Straightening Existing Bullet List Hierarchies
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

If you invoke ``rst-straighten-bullets-region`` (C-c C-w), the
existing bullets in the highlighted region will be replaced to reflect
their respective level.  This does not make a difference in the
document structure that reStructuredText_ defines, but looks better in
the input file, for example, if all of the top-level bullet items use
the character ``-``, and all of the 2nd level items use ``*``, etc.


Creating and Removing Line Blocks
---------------------------------

To create line blocks, first select the region to convert and invoke
``rst-toggle-line-block`` with ``C-c C-d``, for example, the
following::

  Apples
  Oranges
  Bananas

becomes::

  | Apples
  | Oranges
  | Bananas

This works even if the region is indented.  To remove line blocks,
select a region and invoke with a prefix argument.


Commenting a Region of Text
---------------------------

If you use the Emacs ``comment-region`` function (bound to ``C-c
C-c``), the appropriate comment syntax will be added to the active
block of text::

  Apples
  Oranges
  Bananas

becomes::

  .. Apples
  .. Oranges
  .. Bananas



Converting Documents from Emacs
===============================

The major mode provides a number of functions for running documents
being edited through the docutils tools.

The main generic function is ``rst-compile`` (``C-c 1``). This
function basically creates a compilation command with the correct
output name for the current buffer and then invokes Emacs' compile
function.  It also looks for the presence of a ``docutils.conf``
configuration file in the parent directories and adds it to the
cmdline options. There is also an alternative function in case you
often need run your document in a second toolset (``C-c 2``).

You can customize the commands being used by setting
``rst-compile-primary-toolset`` and ``rst-compile-secondary-toolset``.

Other commands are available for other formats:

- ``rst-compile-pseudo-region`` (``C-c 3``): When crafting documents,
  it is often convenient to view which data structures docutils will
  parse them into. You can use to run the active region through
  ``rst2pseudoxml.py`` and have the output automatically be displayed
  in a new buffer.
  
- ``rst-compile-pdf-preview`` (``C-c 4``): Convert the current
  document to PDF and launch a viewer on the results.
  
- ``rst-compile-slides-preview`` (``C-c 5``): Convert the current
  document to S5 slides and view in a web browser.


Table-of-Contents Features
==========================

When you are editing long documents, it can be a bit difficult to
orient yourself in the structure of your text.  To that effect, a
function is provided that quickly parses the document and presents a
hierarchically indented table of contents of the document in a
temporary buffer, in which you can navigate and press ``Return`` to go
to a specific section.

Invoke this function (``rst-toc``) with ``C-c C-t``.  It should
present a temporary buffer that looks something like this::

  Table of Contents:
  Debugging Meta-Techniques
    Introduction
    Debugging Solution Patterns
      Recognize That a Bug Exists
      Subdivide and Isolate
      Identify and Verify Assumptions
      Use a Tool for Introspection
      Change one thing at a time
      Learn about the System
    Understanding a bug
    The Basic Steps in Debugging
    Attitude
      Bad Feelings
      Good Feelings
    References

When you select a section title (press ``RET``), the temporary buffer
disappears and you are left with the cursor positioned at the chosen
section.


Inserting a Table of Contents
-----------------------------

Oftentimes in long text documents that are meant to be read directly,
a Table of Contents is inserted at the beginning of the text.  This is
the case for most internet FAQs, for example.  In reStructuredText_
documents, since the table of contents is automatically generated by
the parser with the ``.. contents::`` directive, people generally have
not been adding a text table of contents to their source documents,
and partly because it is too much trouble to edit and maintain.

The emacs support for reStructuredText_ provides a function to insert
such a table of contents in your document.  Since it is not meant to
be part of the document text, you should place such a table of
contents within a comment, so that it is ignored by the parser.  This
is the favoured usage::

  .. contents::
  ..
      1  Introduction
      2  Debugging Solution Patterns
        2.1  Recognize That a Bug Exists
        2.2  Subdivide and Isolate
        2.3  Identify and Verify Assumptions
        2.4  Use a Tool for Introspection
        2.5  Change one thing at a time
        2.6  Learn about the System
      3  Understanding a bug
      4  The Basic Steps in Debugging
      5  Attitude
        5.1  Bad Feelings
        5.2  Good Feelings
      6  References

Just place the cursor at the top-left corner where you want to insert
the TOC and invoke the function with ``C-c C-i``.  The table of
contents will display all the section titles that are under the
location where the insertion occurs.  This way you can insert local
table of contents by placing them in the appropriate location.

If you have deep nesting of sections, you can use a numeric prefix
argument to limit the depth of rendering of the TOC.

You can also customize the look of the TOC by setting the values of
the following variables:: ``rst-toc-indent``,
``rst-toc-insert-style``, ``rst-toc-insert-max-level``.

.. note:: 

   The table-of-contents inserted by ``rst-mode`` has text properties
   added to it so that if you type ``C-c C-f`` while the cursor is on
   one of its entries, the cursor will jump to the corresponding
   section in the document.
   

Maintaining the Table of Contents Up-to-date
--------------------------------------------

One issue is that you will probably want to maintain the inserted
table of contents up-to-date.  There is a function that will
automatically look for the inserted TOC (``rst-toc-update``)
and it can be added to a hook on the section decoration adjustment
function, so that every time you adjust a section title, the TOC is
updated. Add this functionality with the following emacs
configuration::

  (add-hook 'rst-adjust-hook 'rst-toc-update)

You can invoke the update on the current buffer with ``C-c C-u``.


Syntax Highlighting via Font-Lock
=================================

``rst-mode`` also provides syntax highlighting to reStructuredText_
constructs. (This mode was written by Stefan Merten.)

Lazy syntax coloring is implemented for many of the constructs that
reStructuredText_ prescribes. By default, the font-lock colouring is
performed lazily. If you don't like this, you can turn this off by
setting the value of ``rst-mode-lazy``. You can also change the
various colours (see the source file for the whole list of
customizable faces).

``font-lock`` syntax highlighting is enabled by default. If you prefer
to turn off syntax highlighting (on some machines it can slow down
editing a little bit), you can use the following in your Emacs
configuration::

  (setq font-lock-global-modes '(not rst-mode))


Face Customization
------------------

The ``rst-faces`` group contains all necessary for customizing
fonts. The default settings use standard ``font-lock-*-face`` so if
you set these to your liking they are probably good in rst-mode also.

The group is contained in the faces group as well as in the rst group.


Default Fonts
~~~~~~~~~~~~~

The ``rst-faces-defaults`` group contains all necessary for
customizing the default fonts used for section title faces.

The general idea for section title faces is to have a non-default
background but do not change the background. The section level is
shown by the lightness of the background color. If you like this
general idea of generating faces for section titles but do not like
the details this group is the point where you can customize the
details. If you do not like the general idea, however, you should
customize the faces used in ``rst-adornment-faces-alist``.

Note: If you are using a dark background please make sure the variable
``frame-background-mode`` is set to the symbol dark. This triggers
some default values which are probably right for you.

The group is contained in the ``rst-faces`` group.

All customizable features have a comment explaining their
meaning. Refer to the customization of your Emacs (try ``M-x
customize``).



Other Useful Settings
=====================

This section covers general emacs text-mode settings that are useful
in the context of reStructuredText_ conventions.  These are not
provided by ``rst.el`` but you may find them useful specifically for
reStructuredText_ documents.

``text-mode`` Settings
----------------------

Consult the Emacs manual for more text-mode customizations.  In
particular, you may be interested in setting the following variables,
functions and modes that pertain somewhat to text-mode:

- indent-tabs-mode
- colon-double-space
- auto-fill-mode
- auto-mode-alist
- fill-region

Editing Tables: Emacs table mode
--------------------------------

You may want to check out `Emacs table mode`_ to create an edit
tables, it allows creating ascii tables compatible with
reStructuredText_.

.. _Emacs table mode: http://table.sourceforge.net/


Character Processing
--------------------

Since reStructuredText punts on the issue of character processing,
here are some useful resources for Emacs users in the Unicode world:

* `xmlunicode.el and unichars.el from Norman Walsh
  <http://nwalsh.com/emacs/xmlchars/index.html>`__

* `An essay by Tim Bray, with example code
  <http://www.tbray.org/ongoing/When/200x/2003/09/27/UniEmacs>`__

* For Emacs users on Mac OS X, here are some useful useful additions
  to your .emacs file.

  - To get direct keyboard input of non-ASCII characters (like
    "option-e e" resulting in "é" [eacute]), first enable the option
    key by setting the command key as your meta key::

        (setq mac-command-key-is-meta t) ;; nil for option key

    Next, use one of these lines::

        (set-keyboard-coding-system 'mac-roman)
        (setq mac-keyboard-text-encoding kTextEncodingISOLatin1)

    I prefer the first line, because it enables non-Latin-1 characters
    as well (em-dash, curly quotes, etc.).

  - To enable the display of all characters in the Mac-Roman charset,
    first create a fontset listing the fonts to use for each range of
    characters using charsets that Emacs understands::

      (create-fontset-from-fontset-spec
       "-apple-monaco-medium-r-normal--10-*-*-*-*-*-fontset-monaco,
        ascii:-apple-monaco-medium-r-normal--10-100-75-75-m-100-mac-roman,
        latin-iso8859-1:-apple-monaco-medium-r-normal--10-100-75-75-m-100-mac-roman,
        mule-unicode-0100-24ff:-apple-monaco-medium-r-normal--10-100-75-75-m-100-mac-roman")

    Latin-1 doesn't cover characters like em-dash and curly quotes, so
    "mule-unicode-0100-24ff" is needed.

    Next, use that fontset::

        (set-frame-font "fontset-monaco")

  - To enable cooperation between the system clipboard and the Emacs
    kill ring, add this line::

        (set-clipboard-coding-system 'mac-roman)

  Other useful resources are in `Andrew Choi's Emacs 21 for Mac OS X
  FAQ <http://members.shaw.ca/akochoi-emacs/stories/faq.html>`__.

No matter what platform (or editor) you're using, I recommend the
ProFont__ programmer's font.  It's monospaced, small but readable,
similar characters are visually distinctive (like "I1l|", "0O", "ao",
and ".,:;"), and free.

__ http://www.tobias-jung.de/seekingprofont/



Credits
=======

- The automatic section adjustment and table of contents features were
  written by Martin Blais;
- Syntax highlighting was implemented by Stefan Merten;
- Various other functions were implemented by David Goodger.

Obsolete Files
--------------

On 2005-10-30, ``rst.el`` integrated and replaced the contents of the
following files:

- ``restructuredtext.el``
- ``rst-html.el``
- ``rst-mode.el`` 



.. _Emacs: http://www.gnu.org/software/emacs/emacs.html
.. _reStructuredText: http://docutils.sf.net/rst.html


..
   Local Variables:
   mode: rst
   indent-tabs-mode: nil
   sentence-end-double-space: t
   fill-column: 70
   End: