
reStructuredText Primer
***********************

This section is a brief introduction to reStructuredText (reST)
concepts and syntax, intended to provide authors with enough
information to author documents productively.  Since reST was designed
to be a simple, unobtrusive markup language, this will not take too
long.

See also:

   The authoritative reStructuredText User Documentation.


Paragraphs
==========

The paragraph is the most basic block in a reST document.  Paragraphs
are simply chunks of text separated by one or more blank lines.  As in
Python, indentation is significant in reST, so all lines of the same
paragraph must be left-aligned to the same level of indentation.


Inline markup
=============

The standard reST inline markup is quite simple: use

* one asterisk: ``*text*`` for emphasis (italics),

* two asterisks: ``**text**`` for strong emphasis (boldface), and

* backquotes: ````text```` for code samples.

If asterisks or backquotes appear in running text and could be
confused with inline markup delimiters, they have to be escaped with a
backslash.

Be aware of some restrictions of this markup:

* it may not be nested,

* content may not start or end with whitespace: ``* text*`` is wrong,

* it must be separated from surrounding text by non-word characters.
  Use a backslash escaped space to work around that: ``thisis\ *one*\
  word``.

These restrictions may be lifted in future versions of the docutils.

reST also allows for custom "interpreted text roles"', which signify
that the enclosed text should be interpreted in a specific way.
Sphinx uses this to provide semantic markup and cross-referencing of
identifiers, as described in the appropriate section.  The general
syntax is ``:rolename:`content```.


Lists and Quotes
================

List markup is natural: just place an asterisk at the start of a
paragraph and indent properly.  The same goes for numbered lists; they
can also be autonumbered using a ``#`` sign:

   * This is a bulleted list.
   * It has two items, the second
     item uses two lines.

   1. This is a numbered list.
   2. It has two items too.

   #. This is a numbered list.
   #. It has two items too.

Nested lists are possible, but be aware that they must be separated
from the parent list items by blank lines:

   * this is
   * a list

     * with a nested list
     * and some subitems

   * and here the parent list continues

Definition lists are created as follows:

   term (up to a line of text)
      Definition of the term, which must be indented

      and can even consist of multiple paragraphs

   next term
      Description.

Paragraphs are quoted by just indenting them more than the surrounding
paragraphs.


Source Code
===========

Literal code blocks are introduced by ending a paragraph with the
special marker ``::``.  The literal block must be indented:

   This is a normal text paragraph. The next paragraph is a code sample::

      It is not processed in any way, except
      that the indentation is removed.

      It can span multiple lines.

   This is a normal text paragraph again.

The handling of the ``::`` marker is smart:

* If it occurs as a paragraph of its own, that paragraph is completely
  left out of the document.

* If it is preceded by whitespace, the marker is removed.

* If it is preceded by non-whitespace, the marker is replaced by a
  single colon.

That way, the second sentence in the above example's first paragraph
would be rendered as "The next paragraph is a code sample:".


Hyperlinks
==========


External links
--------------

Use ```Link text <http://target>`_`` for inline web links.  If the
link text should be the web address, you don't need special markup at
all, the parser finds links and mail addresses in ordinary text.


Internal links
--------------

Internal linking is done via a special reST role, see the section on
specific markup, *Cross-linking markup*.


Sections
========

Section headers are created by underlining (and optionally overlining)
the section title with a punctuation character, at least as long as
the text:

   =================
   This is a heading
   =================

Normally, there are no heading levels assigned to certain characters
as the structure is determined from the succession of headings.
However, for the Python documentation, we use this convention:

* ``#`` with overline, for parts

* ``*`` with overline, for chapters

* ``=``, for sections

* ``-``, for subsections

* ``^``, for subsubsections

* ``"``, for paragraphs


Explicit Markup
===============

"Explicit markup" is used in reST for most constructs that need
special handling, such as footnotes, specially-highlighted paragraphs,
comments, and generic directives.

An explicit markup block begins with a line starting with ``..``
followed by whitespace and is terminated by the next paragraph at the
same level of indentation.  (There needs to be a blank line between
explicit markup and normal paragraphs.  This may all sound a bit
complicated, but it is intuitive enough when you write it.)


Directives
==========

A directive is a generic block of explicit markup.  Besides roles, it
is one of the extension mechanisms of reST, and Sphinx makes heavy use
of it.

Basically, a directive consists of a name, arguments, options and
content. (Keep this terminology in mind, it is used in the next
chapter describing custom directives.)  Looking at this example,

   .. function:: foo(x)
                 foo(y, z)
      :bar: no

      Return a line of text input from the user.

``function`` is the directive name.  It is given two arguments here,
the remainder of the first line and the second line, as well as one
option ``bar`` (as you can see, options are given in the lines
immediately following the arguments and indicated by the colons).

The directive content follows after a blank line and is indented
relative to the directive start.


Footnotes
=========

For footnotes, use ``[#]_`` to mark the footnote location, and add the
footnote body at the bottom of the document after a "Footnotes" rubric
heading, like so:

   Lorem ipsum [#]_ dolor sit amet ... [#]_

   .. rubric:: Footnotes

   .. [#] Text of the first footnote.
   .. [#] Text of the second footnote.

You can also explicitly number the footnotes for better context.


Comments
========

Every explicit markup block which isn't a valid markup construct (like
the footnotes above) is regarded as a comment.


Source encoding
===============

Since the easiest way to include special characters like em dashes or
copyright signs in reST is to directly write them as Unicode
characters, one has to specify an encoding:

All Python documentation source files must be in UTF-8 encoding, and
the HTML documents written from them will be in that encoding as well.


Gotchas
=======

There are some problems one commonly runs into while authoring reST
documents:

* **Separation of inline markup:** As said above, inline markup spans
  must be separated from the surrounding text by non-word characters,
  you have to use an escaped space to get around that.
