path: root/README

% Pandoc User's Guide
% John MacFarlane
% July 15, 2015

Synopsis
========

`pandoc` [*options*] [*input-file*]...

Description
===========

Pandoc is a [Haskell] library for converting from one markup format to
another, and a command-line tool that uses this library. It can read
[Markdown], [CommonMark], [PHP Markdown Extra], [GitHub-Flavored Markdown],
and (subsets of) [Textile], [reStructuredText], [HTML], [LaTeX], [MediaWiki markup], [TWiki
markup], [Haddock markup], [OPML], [Emacs Org mode], [DocBook],
[txt2tags], [EPUB], [ODT] and [Word docx]; and it can write plain text,
[Markdown], [CommonMark], [PHP Markdown Extra], [GitHub-Flavored Markdown],
[reStructuredText], [XHTML], [HTML5], [LaTeX] (including
[`beamer`] slide shows), [ConTeXt], [RTF], [OPML], [DocBook],
[OpenDocument], [ODT], [Word docx], [GNU Texinfo], [MediaWiki markup],
[DokuWiki markup], [Haddock markup], [EPUB] (v2 or v3),
[FictionBook2], [Textile], [groff man] pages, [Emacs Org mode],
[AsciiDoc], [InDesign ICML], and [Slidy], [Slideous], [DZSlides],
[reveal.js] or [S5] HTML slide shows. It can also produce [PDF] output
on systems where LaTeX is installed.

Pandoc's enhanced version of markdown includes syntax for [footnotes],
[tables], flexible [ordered lists], [definition lists], [fenced code blocks],
[superscripts and subscripts], [strikeout], [metadata blocks], automatic tables of
contents, [embedded LaTeX math][Math rendering in HTML], [citations], and [markdown inside HTML block
elements][Extension: `markdown_in_html_blocks`]. (These enhancements, described below under
[Pandoc's markdown], can be disabled using the
`markdown_strict` input or output format.)

In contrast to most existing tools for converting markdown to HTML, which
use regex substitutions, Pandoc has a modular design: it consists of a
set of readers, which parse text in a given format and produce a native
representation of the document, and a set of writers, which convert
this native representation into a target format. Thus, adding an input
or output format requires only adding a reader or writer.

Because Pandoc's intermediate representation of a document is less
expressive than many of the formats it converts between, one should
not expect perfect conversions between every format and every other.
Pandoc attempts to preserve the structural elements of a document, but
not formatting details such as margin size.  And some document elements,
such as complex tables, may not fit into Pandoc's simple document
model.  While conversions from Pandoc's Markdown to all formats aspire
to be perfect, conversions from formats more expressive than Pandoc's
Markdown can be expected to be lossy.

[markdown]: http://daringfireball.net/projects/markdown/
[CommonMark]: http://commonmark.org
[PHP Markdown Extra]: https://michelf.ca/projects/php-markdown/extra/
[GitHub-Flavored Markdown]: https://help.github.com/articles/github-flavored-markdown/
[reStructuredText]: http://docutils.sourceforge.net/docs/ref/rst/introduction.html
[S5]: http://meyerweb.com/eric/tools/s5/
[Slidy]: http://www.w3.org/Talks/Tools/Slidy/
[Slideous]: http://goessner.net/articles/slideous/
[HTML]: http://www.w3.org/html/
[HTML5]: http://www.w3.org/TR/html5/
[XHTML]: http://www.w3.org/TR/xhtml1/
[LaTeX]: http://latex-project.org
[`beamer`]: https://ctan.org/pkg/beamer
[Beamer User's Guide]: http://ctan.math.utah.edu/ctan/tex-archive/macros/latex/contrib/beamer/doc/beameruserguide.pdf
[ConTeXt]: http://pragma-ade.nl
[RTF]: http://en.wikipedia.org/wiki/Rich_Text_Format
[DocBook]: http://docbook.org
[txt2tags]: http://txt2tags.org
[EPUB]: http://idpf.org/epub
[OPML]: http://dev.opml.org/spec2.html
[OpenDocument]: http://opendocument.xml.org
[ODT]: http://en.wikipedia.org/wiki/OpenDocument
[Textile]: http://redcloth.org/textile
[MediaWiki markup]: https://www.mediawiki.org/wiki/Help:Formatting
[DokuWiki markup]: https://www.dokuwiki.org/dokuwiki
[TWiki markup]: http://twiki.org/cgi-bin/view/TWiki/TextFormattingRules
[Haddock markup]: https://www.haskell.org/haddock/doc/html/ch03s08.html
[groff man]: http://developer.apple.com/DOCUMENTATION/Darwin/Reference/ManPages/man7/groff_man.7.html
[Haskell]: https://www.haskell.org
[GNU Texinfo]: http://www.gnu.org/software/texinfo/
[Emacs Org mode]: http://orgmode.org
[AsciiDoc]: http://www.methods.co.nz/asciidoc/
[DZSlides]: http://paulrouget.com/dzslides/
[Word docx]: http://www.microsoft.com/interop/openup/openxml/default.aspx
[PDF]: https://www.adobe.com/pdf/
[reveal.js]: http://lab.hakim.se/reveal-js/
[FictionBook2]: http://www.fictionbook.org/index.php/Eng:XML_Schema_Fictionbook_2.1
[InDesign ICML]: https://www.adobe.com/content/dam/Adobe/en/devnet/indesign/cs55-docs/IDML/idml-specification.pdf

Using `pandoc`
--------------

If no *input-file* is specified, input is read from *stdin*.
Otherwise, the *input-files* are concatenated (with a blank
line between each) and used as input.  Output goes to *stdout* by
default (though output to *stdout* is disabled for the `odt`, `docx`,
`epub`, and `epub3` output formats).  For output to a file, use the
`-o` option:

    pandoc -o output.html input.txt

By default, pandoc produces a document fragment, not a standalone
document with a proper header and footer.  To produce a standalone
document, use the `-s` or `--standalone` flag:

    pandoc -s -o output.html input.txt

For more information on how standalone documents are produced, see
[Templates], below.

Instead of a file, an absolute URI may be given.  In this case
pandoc will fetch the content using HTTP:

    pandoc -f html -t markdown http://www.fsf.org

If multiple input files are given, `pandoc` will concatenate them all (with
blank lines between them) before parsing. This feature is disabled for
 binary input formats such as `EPUB`, `odt`, and `docx`.

The format of the input and output can be specified explicitly using
command-line options.  The input format can be specified using the
`-r/--read` or `-f/--from` options, the output format using the
`-w/--write` or `-t/--to` options.  Thus, to convert `hello.txt` from
markdown to LaTeX, you could type:

    pandoc -f markdown -t latex hello.txt

To convert `hello.html` from HTML to markdown:

    pandoc -f html -t markdown hello.html

Supported output formats are listed below under the `-t/--to` option.
Supported input formats are listed below under the `-f/--from` option. Note
that the `rst`, `textile`, `latex`, and `html` readers are not complete;
there are some constructs that they do not parse.

If the input or output format is not specified explicitly, `pandoc`
will attempt to guess it from the extensions of
the input and output filenames.  Thus, for example,

    pandoc -o hello.tex hello.txt

will convert `hello.txt` from markdown to LaTeX.  If no output file
is specified (so that output goes to *stdout*), or if the output file's
extension is unknown, the output format will default to HTML.
If no input file is specified (so that input comes from *stdin*), or
if the input files' extensions are unknown, the input format will
be assumed to be markdown unless explicitly specified.

Pandoc uses the UTF-8 character encoding for both input and output.
If your local character encoding is not UTF-8, you
should pipe input and output through [`iconv`]:

    iconv -t utf-8 input.txt | pandoc | iconv -f utf-8

Note that in some output formats (such as HTML, LaTeX, ConTeXt,
RTF, OPML, DocBook, and Texinfo), information about
the character encoding is included in the document header, which
will only be included if you use the `-s/--standalone` option.

[`iconv`]: http://www.gnu.org/software/libiconv/

Creating a PDF
--------------

To produce a PDF, specify an output file with a `.pdf` extension.
Pandoc will use LaTeX to convert it to PDF:

    pandoc test.txt -o test.pdf

Production of a PDF requires that a LaTeX engine be installed (see
`--latex-engine`, below), and assumes that the following LaTeX packages
are available: [`amsfonts`], [`amsmath`], [`lm`],
[`ifxetex`], [`ifluatex`], [`eurosym`], [`listings`] (if the
`--listings` option is used), [`fancyvrb`], [`longtable`],
[`booktabs`], [`url`], [`graphicx`] and [`grffile`] (if the
document contains images), [`color`], [`hyperref`], [`ulem`],
[`geometry`] (with the `geometry` variable set), [`setspace`] (with
`linestretch`), and [`babel`] (with `lang`). The use of `xelatex` or
`lualatex` as the LaTeX engine requires [`fontspec`]; `xelatex` uses
[`mathspec`], [`polyglossia`] (with `lang`), [`xecjk`], and
[`bidi`] (with the `dir` variable set). The [`upquote`] and
[`microtype`] packages are used if available, and [`csquotes`] will
be used for [smart punctuation] if added to the template. The
[`natbib`], [`biblatex`], [`bibtex`], and [`biber`] packages can
optionally be used for [citation rendering]. These are included with
all recent versions of [TeX Live].

PDF output can be controlled using [variables for LaTeX].

[`amsfonts`]: https://ctan.org/pkg/amsfonts
[`amsmath`]: https://ctan.org/pkg/amsmath
[`lm`]: https://ctan.org/pkg/lm
[`ifxetex`]: https://ctan.org/pkg/ifxetex
[`ifluatex`]: https://ctan.org/pkg/ifluatex
[`eurosym`]: https://ctan.org/pkg/eurosym
[`listings`]: https://ctan.org/pkg/listings
[`fancyvrb`]: https://ctan.org/pkg/fancyvrb
[`longtable`]: https://ctan.org/pkg/longtable
[`booktabs`]: https://ctan.org/pkg/booktabs
[`url`]: https://ctan.org/pkg/url
[`graphicx`]: https://ctan.org/pkg/graphicx
[`grffile`]: https://ctan.org/pkg/grffile
[`geometry`]: https://ctan.org/pkg/geometry
[`setspace`]: https://ctan.org/pkg/setspace
[`color`]: http://ctan.org/pkg/color
[`xecjk`]: https://ctan.org/pkg/xecjk
[`hyperref`]: https://ctan.org/pkg/hyperref
[`ulem`]: https://ctan.org/pkg/ulem
[`babel`]: https://ctan.org/pkg/babel
[`bidi`]: https://ctan.org/pkg/bidi
[`mathspec`]: https://ctan.org/pkg/mathspec
[`polyglossia`]: https://ctan.org/pkg/polyglossia
[`fontspec`]: https://ctan.org/pkg/fontspec
[`upquote`]: https://ctan.org/pkg/upquote
[`microtype`]: https://ctan.org/pkg/microtype
[`csquotes`]: https://ctan.org/pkg/csquotes
[`natbib`]: https://ctan.org/pkg/natbib
[`biblatex`]: https://ctan.org/pkg/biblatex
[`bibtex`]: https://ctan.org/pkg/bibtex
[`biber`]: https://ctan.org/pkg/biber
[TeX Live]: http://www.tug.org/texlive/

`hsmarkdown`
------------

A user who wants a drop-in replacement for `Markdown.pl` may create
a symbolic link to the `pandoc` executable called `hsmarkdown`. When
invoked under the name `hsmarkdown`, `pandoc` will behave as if
invoked with `-f markdown_strict --email-obfuscation=references`,
and all command-line options will be treated as regular arguments.
This approach does not work under [Cygwin], due to problems with
its simulation of symbolic links.

[Cygwin]: https://cygwin.com

Options
=======

General options
---------------

`-f` *FORMAT*, `-r` *FORMAT*, `--from=`*FORMAT*, `--read=`*FORMAT*

:   Specify input format.  *FORMAT* can be `native` (native Haskell),
    `json` (JSON version of native AST), `markdown` (pandoc's
    extended markdown), `markdown_strict` (original unextended
    markdown), `markdown_phpextra` (PHP Markdown Extra),
    `markdown_github` (GitHub-Flavored Markdown),
    `commonmark` (CommonMark markdown), `textile` (Textile), `rst`
    (reStructuredText), `html` (HTML), `docbook` (DocBook), `t2t`
    (txt2tags), `docx` (docx), `odt` (ODT), `epub` (EPUB), `opml` (OPML),
    `org` (Emacs Org mode), `mediawiki` (MediaWiki markup), `twiki` (TWiki
    markup), `haddock` (Haddock markup), or `latex` (LaTeX).  If
    `+lhs` is appended to `markdown`, `rst`, `latex`, or `html`, the
    input will be treated as literate Haskell source: see [Literate
    Haskell support], below. Markdown
    syntax extensions can be individually enabled or disabled by
    appending `+EXTENSION` or `-EXTENSION` to the format name. So, for
    example, `markdown_strict+footnotes+definition_lists` is strict
    markdown with footnotes and definition lists enabled, and
    `markdown-pipe_tables+hard_line_breaks` is pandoc's markdown
    without pipe tables and with hard line breaks. See [Pandoc's
    markdown], below, for a list of extensions and
    their names.

`-t` *FORMAT*, `-w` *FORMAT*, `--to=`*FORMAT*, `--write=`*FORMAT*

:   Specify output format.  *FORMAT* can be `native` (native Haskell),
    `json` (JSON version of native AST), `plain` (plain text),
    `markdown` (pandoc's extended markdown), `markdown_strict`
    (original unextended markdown), `markdown_phpextra` (PHP Markdown
    Extra), `markdown_github` (GitHub-Flavored
    Markdown), `commonmark` (CommonMark markdown), `rst`
    (reStructuredText), `html` (XHTML), `html5` (HTML5), `latex`
    (LaTeX), `beamer` (LaTeX beamer slide show), `context` (ConTeXt),
    `man` (groff man), `mediawiki` (MediaWiki markup), `dokuwiki`
    (DokuWiki markup), `textile` (Textile), `org` (Emacs Org mode),
    `texinfo` (GNU Texinfo), `opml` (OPML), `docbook` (DocBook),
    `opendocument` (OpenDocument), `odt` (OpenOffice text document),
    `docx` (Word docx), `haddock` (Haddock markup), `rtf` (rich text
    format), `epub` (EPUB v2 book), `epub3` (EPUB v3), `fb2`
    (FictionBook2 e-book), `asciidoc` (AsciiDoc), `icml` (InDesign
    ICML), `slidy` (Slidy HTML and javascript slide show), `slideous`
    (Slideous HTML and javascript slide show), `dzslides` (DZSlides
    HTML5 + javascript slide show), `revealjs` (reveal.js HTML5 +
    javascript slide show), `s5` (S5 HTML and javascript slide show),
    or the path of a custom lua writer (see [Custom
    writers], below). Note that `odt`, `epub`, and
    `epub3` output will not be directed to *stdout*; an output
    filename must be specified using the `-o/--output` option. If
    `+lhs` is appended to `markdown`, `rst`, `latex`, `beamer`,
    `html`, or `html5`, the output will be rendered as literate
    Haskell source: see [Literate Haskell
    support], below.  Markdown syntax
    extensions can be individually enabled or disabled by appending
    `+EXTENSION` or `-EXTENSION` to the format name, as described
    above under `-f`.

`-o` *FILE*, `--output=`*FILE*

:   Write output to *FILE* instead of *stdout*.  If *FILE* is
    `-`, output will go to *stdout*.  (Exception: if the output
    format is `odt`, `docx`, `epub`, or `epub3`, output to stdout is disabled.)

`--data-dir=`*DIRECTORY*

:   Specify the user data directory to search for pandoc data files.
    If this option is not specified, the default user data directory
    will be used.  This is, in Unix:

        $HOME/.pandoc

    in Windows XP:

        C:\Documents And Settings\USERNAME\Application Data\pandoc

    and in Windows Vista or later:

        C:\Users\USERNAME\AppData\Roaming\pandoc

    You can find the default user data directory on your system by
    looking at the output of `pandoc --version`.
    A `reference.odt`, `reference.docx`, `epub.css`, `templates`,
    `slidy`, `slideous`, or `s5` directory
    placed in this directory will override pandoc's normal defaults.

`--bash-completion`

:   Generate a bash completion script.  To enable bash completion
    with pandoc, add this to your `.bashrc`:

         eval "$(pandoc --bash-completion)"

`--verbose`

:   Give verbose debugging output.  Currently this only has an effect
    with PDF output.

`-v`, `--version`

:   Print version.

`-h`, `--help`

:   Show usage message.

Reader options
--------------

`-R`, `--parse-raw`

:   Parse untranslatable HTML codes and LaTeX environments as raw HTML
    or LaTeX, instead of ignoring them.  Affects only HTML and LaTeX
    input. Raw HTML can be printed in markdown, reStructuredText, HTML,
    Slidy, Slideous, DZSlides, reveal.js, and S5 output; raw LaTeX
    can be printed in markdown, reStructuredText, LaTeX, and ConTeXt output.
    The default is for the readers to omit untranslatable HTML codes and
    LaTeX environments.  (The LaTeX reader does pass through untranslatable
    LaTeX *commands*, even if `-R` is not specified.)

`-S`, `--smart`

:   Produce typographically correct output, converting straight quotes
    to curly quotes, `---` to em-dashes, `--` to en-dashes, and
    `...` to ellipses. Nonbreaking spaces are inserted after certain
    abbreviations, such as "Mr." (Note: This option is significant only when
    the input format is `markdown`, `markdown_strict`, `textile` or `twiki`.
    It is selected automatically when the input format is `textile` or the
    output format is `latex` or `context`, unless `--no-tex-ligatures`
    is used.)

`--old-dashes`

:   Selects the pandoc <= 1.8.2.1 behavior for parsing smart dashes: `-` before
    a numeral is an en-dash, and `--` is an em-dash.  This option is selected
    automatically for `textile` input.

`--base-header-level=`*NUMBER*

:   Specify the base level for headers (defaults to 1).

`--indented-code-classes=`*CLASSES*

:   Specify classes to use for indented code blocks--for example,
    `perl,numberLines` or `haskell`. Multiple classes may be separated
    by spaces or commas.

`--default-image-extension=`*EXTENSION*

:   Specify a default extension to use when image paths/URLs have no
    extension.  This allows you to use the same source for formats that
    require different kinds of images.  Currently this option only affects
    the markdown and LaTeX readers.

`--filter=`*EXECUTABLE*

:   Specify an executable to be used as a filter transforming the
    Pandoc AST after the input is parsed and before the output is
    written.  The executable should read JSON from stdin and write
    JSON to stdout.  The JSON must be formatted like  pandoc's own
    JSON input and output.  The name of the output format will be
    passed to the filter as the first argument.  Hence,

        pandoc --filter ./caps.py -t latex

    is equivalent to

        pandoc -t json | ./caps.py latex | pandoc -f json -t latex

    The latter form may be useful for debugging filters.

    Filters may be written in any language.  `Text.Pandoc.JSON`
    exports `toJSONFilter` to facilitate writing filters in Haskell.
    Those who would prefer to write filters in python can use the
    module [`pandocfilters`], installable from PyPI. There are also
    pandoc filter libraries in [PHP], [perl], and [javascript/node.js].

    Note that the *EXECUTABLE* will be sought in the user's
    `PATH`, and not in the working directory, if no directory is
    provided.  If you want to run a script in the working directory,
    preface the filename with `./`.

`-M` *KEY*[`=`*VAL*], `--metadata=`*KEY*[`:`*VAL*]

:   Set the metadata field *KEY* to the value *VAL*.  A value specified
    on the command line overrides a value specified in the document.
    Values will be parsed as YAML boolean or string values. If no value is
    specified, the value will be treated as Boolean true.  Like
    `--variable`, `--metadata` causes template variables to be set.
    But unlike `--variable`, `--metadata` affects the metadata of the
    underlying document (which is accessible from filters and may be
    printed in some output formats).

`--normalize`

:   Normalize the document after reading:  merge adjacent
    `Str` or `Emph` elements, for example, and remove repeated `Space`s.

`-p`, `--preserve-tabs`

:   Preserve tabs instead of converting them to spaces (the default).
    Note that this will only affect tabs in literal code spans and code
    blocks; tabs in regular text will be treated as spaces.

`--tab-stop=`*NUMBER*

:   Specify the number of spaces per tab (default is 4).

`--track-changes=accept`|`reject`|`all`

:   Specifies what to do with insertions and deletions produced by the MS
    Word "Track Changes" feature.  `accept` (the default), inserts all
    insertions, and ignores all deletions. `reject` inserts all
    deletions and ignores insertions. `all` puts in both insertions
    and deletions, wrapped in spans with `insertion` and `deletion`
    classes, respectively. The author and time of change is
    included. `all` is useful for scripting: only accepting changes
    from a certain reviewer, say, or before a certain date. This
    option only affects the docx reader.

`--extract-media=`*DIR*

:   Extract images and other media contained in a docx or epub container
    to the path *DIR*, creating it if necessary, and adjust the images
    references in the document so they point to the extracted files.
    This option only affects the docx and epub readers.

[`pandocfilters`]: https://github.com/jgm/pandocfilters
[PHP]: https://github.com/vinai/pandocfilters-php
[perl]: https://metacpan.org/pod/Pandoc::Filter
[javascript/node.js]: https://github.com/mvhenderson/pandoc-filter-node

General writer options
----------------------

`-s`, `--standalone`

:   Produce output with an appropriate header and footer (e.g. a
    standalone HTML, LaTeX, or RTF file, not a fragment).  This option
    is set automatically for `pdf`, `epub`, `epub3`, `fb2`, `docx`, and `odt`
    output.

`--template=`*FILE*

:   Use *FILE* as a custom template for the generated document. Implies
    `--standalone`. See [Templates], below, for a description
    of template syntax. If no extension is specified, an extension
    corresponding to the writer will be added, so that `--template=special`
    looks for `special.html` for HTML output.  If the template is not
    found, pandoc will search for it in the `templates` subdirectory of
    the user data directory (see `--data-dir`). If this option is not used,
    a default template appropriate for the output format will be used (see
    `-D/--print-default-template`).

`-V` *KEY*[`=`*VAL*], `--variable=`*KEY*[`:`*VAL*]

:   Set the template variable *KEY* to the value *VAL* when rendering the
    document in standalone mode. This is generally only useful when the
    `--template` option is used to specify a custom template, since
    pandoc automatically sets the variables used in the default
    templates.  If no *VAL* is specified, the key will be given the
    value `true`.

`-D` *FORMAT*, `--print-default-template=`*FORMAT*

:   Print the system default template for an output *FORMAT*. (See `-t`
    for a list of possible *FORMAT*s.)  Templates in the user data
    directory are ignored.

`--print-default-data-file=`*FILE*

:   Print a system default data file.  Files in the user data directory
    are ignored.

`--no-wrap`

:   Disable text wrapping in output. By default, text is wrapped
    appropriately for the output format.

`--columns=`*NUMBER*

:   Specify length of lines in characters (for text wrapping).

`--toc`, `--table-of-contents`

:   Include an automatically generated table of contents (or, in
    the case of `latex`, `context`, and `rst`, an instruction to create
    one) in the output document. This option has no effect on `man`,
    `docbook`, `slidy`, `slideous`, `s5`, `docx`, or `odt` output.

`--toc-depth=`*NUMBER*

:   Specify the number of section levels to include in the table
    of contents.  The default is 3 (which means that level 1, 2, and 3
    headers will be listed in the contents).

`--no-highlight`

:   Disables syntax highlighting for code blocks and inlines, even when
    a language attribute is given.

`--highlight-style=`*STYLE*

:   Specifies the coloring style to be used in highlighted source code.
    Options are `pygments` (the default), `kate`, `monochrome`,
    `espresso`, `zenburn`, `haddock`, and `tango`.  For more information
    on syntax highlighting in pandoc, see [Syntax highlighting], below.

`-H` *FILE*, `--include-in-header=`*FILE*

:   Include contents of *FILE*, verbatim, at the end of the header.
    This can be used, for example, to include special
    CSS or javascript in HTML documents.  This option can be used
    repeatedly to include multiple files in the header.  They will be
    included in the order specified.  Implies `--standalone`.

`-B` *FILE*, `--include-before-body=`*FILE*

:   Include contents of *FILE*, verbatim, at the beginning of the
    document body (e.g. after the `<body>` tag in HTML, or the
    `\begin{document}` command in LaTeX). This can be used to include
    navigation bars or banners in HTML documents. This option can be
    used repeatedly to include multiple files. They will be included in
    the order specified.  Implies `--standalone`.

`-A` *FILE*, `--include-after-body=`*FILE*

:   Include contents of *FILE*, verbatim, at the end of the document
    body (before the `</body>` tag in HTML, or the
    `\end{document}` command in LaTeX). This option can be be used
    repeatedly to include multiple files. They will be included in the
    order specified.  Implies `--standalone`.

Options affecting specific writers
----------------------------------

`--self-contained`

:   Produce a standalone HTML file with no external dependencies, using
    `data:` URIs to incorporate the contents of linked scripts, stylesheets,
    images, and videos. The resulting file should be "self-contained,"
    in the sense that it needs no external files and no net access to be
    displayed properly by a browser. This option works only with HTML output
    formats, including `html`, `html5`, `html+lhs`, `html5+lhs`, `s5`,
    `slidy`, `slideous`, `dzslides`, and `revealjs`. Scripts, images, and
    stylesheets at absolute URLs will be downloaded; those at relative URLs
    will be sought relative to the working directory (if the first source
    file is local) or relative to the base URL (if the first source
    file is remote).  `--self-contained` does not work with `--mathjax`.

`--offline`

:   Deprecated synonym for `--self-contained`.

`-5`, `--html5`

:   Produce HTML5 instead of HTML4.  This option has no effect for writers
    other than `html`. (*Deprecated:*  Use the `html5` output format instead.)

`--html-q-tags`

:   Use `<q>` tags for quotes in HTML.

`--ascii`

:   Use only ascii characters in output.  Currently supported only
    for HTML output (which uses numerical entities instead of
    UTF-8 when this option is selected).

`--reference-links`

:   Use reference-style links, rather than inline links, in writing markdown
    or reStructuredText.  By default inline links are used.

`--atx-headers`

:   Use ATX-style headers in markdown and asciidoc output. The default is
    to use setext-style headers for levels 1-2, and then ATX headers.

`--chapters`

:   Treat top-level headers as chapters in LaTeX, ConTeXt, and DocBook
    output.  When the LaTeX document class is set to `report`, `book`, or
    `memoir`, this option is implied.  If `beamer` is the output
    format, top-level headers will become `\part{..}`.

`-N`, `--number-sections`

:   Number section headings in LaTeX, ConTeXt, HTML, or EPUB output.
    By default, sections are not numbered.  Sections with class
    `unnumbered` will never be numbered, even if `--number-sections`
    is specified.

`--number-offset=`*NUMBER*[`,`*NUMBER*`,`*...*]

:   Offset for section headings in HTML output (ignored in other
    output formats).  The first number is added to the section number for
    top-level headers, the second for second-level headers, and so on.
    So, for example, if you want the first top-level header in your
    document to be numbered "6", specify `--number-offset=5`.
    If your document starts with a level-2 header which you want to
    be numbered "1.5", specify `--number-offset=1,4`.
    Offsets are 0 by default.  Implies `--number-sections`.

`--no-tex-ligatures`

:   Do not convert quotation marks, apostrophes, and dashes to
    the TeX ligatures when writing LaTeX or ConTeXt. Instead, just
    use literal unicode characters. This is needed for using advanced
    OpenType features with `xelatex` and `lualatex`. Note: normally
    `--smart` is selected automatically for LaTeX and ConTeXt
    output, but it must be specified explicitly if `--no-tex-ligatures`
    is selected. If you use literal curly quotes, dashes, and ellipses
    in your source, then you may want to use `--no-tex-ligatures`
    without `--smart`.

`--listings`

:   Use the [`listings`] package for LaTeX code blocks

`-i`, `--incremental`

:   Make list items in slide shows display incrementally (one by one).
    The default is for lists to be displayed all at once.

`--slide-level=`*NUMBER*

:   Specifies that headers with the specified level create
    slides (for `beamer`, `s5`, `slidy`, `slideous`, `dzslides`).  Headers
    above this level in the hierarchy are used to divide the
    slide show into sections; headers below this level create
    subheads within a slide.  The default is to set the slide level
    based on the contents of the document; see
    [Structuring the slide show].

`--section-divs`

:   Wrap sections in `<div>` tags (or `<section>` tags in HTML5),
    and attach identifiers to the enclosing `<div>` (or `<section>`)
    rather than the header itself. See
    [Header identifiers], below.

`--email-obfuscation=none`|`javascript`|`references`

:   Specify a method for obfuscating `mailto:` links in HTML documents.
    `none` leaves `mailto:` links as they are.  `javascript` obfuscates
    them using javascript. `references` obfuscates them by printing their
    letters as decimal or hexadecimal character references.

`--id-prefix=`*STRING*

:   Specify a prefix to be added to all automatically generated identifiers
    in HTML and DocBook output, and to footnote numbers in markdown output.
    This is useful for preventing duplicate identifiers when generating
    fragments to be included in other pages.

`-T` *STRING*, `--title-prefix=`*STRING*

:   Specify *STRING* as a prefix at the beginning of the title
    that appears in the HTML header (but not in the title as it
    appears at the beginning of the HTML body).  Implies
    `--standalone`.

`-c` *URL*, `--css=`*URL*

:   Link to a CSS style sheet. This option can be be used repeatedly to
    include multiple files. They will be included in the order specified.

`--reference-odt=`*FILE*

:   Use the specified file as a style reference in producing an ODT.
    For best results, the reference ODT should be a modified version
    of an ODT produced using pandoc.  The contents of the reference ODT
    are ignored, but its stylesheets are used in the new ODT. If no
    reference ODT is specified on the command line, pandoc will look
    for a file `reference.odt` in the user data directory (see
    `--data-dir`). If this is not found either, sensible defaults will be
    used.

`--reference-docx=`*FILE*

:   Use the specified file as a style reference in producing a docx file.
    For best results, the reference docx should be a modified version
    of a docx file produced using pandoc.  The contents of the reference docx
    are ignored, but its stylesheets and document properties (including
    margins, page size, header, and footer) are used in the new docx. If no
    reference docx is specified on the command line, pandoc will look
    for a file `reference.docx` in the user data directory (see
    `--data-dir`). If this is not found either, sensible defaults will be
    used. The following styles are used by pandoc: [paragraph]
    Normal, Body Text, First Paragraph, Compact, Title, Subtitle, Author, Date,
    Abstract, Bibliography, Heading 1, Heading 2, Heading 3, Heading 4,
    Heading 5, Heading 6, Block Text, Footnote Text, Definition Term,
    Definition, Caption, Table Caption, Image Caption, Figure,
    Figure With Caption, TOC Heading;
    [character] Default Paragraph Font, Body Text Char, Verbatim Char,
    Footnote Reference, Hyperlink; [table] Normal Table.

`--epub-stylesheet=`*FILE*

:   Use the specified CSS file to style the EPUB.  If no stylesheet
    is specified, pandoc will look for a file `epub.css` in the
    user data directory (see `--data-dir`).  If it is not
    found there, sensible defaults will be used.

`--epub-cover-image=`*FILE*

:   Use the specified image as the EPUB cover.  It is recommended
    that the image be less than 1000px in width and height. Note that
    in a markdown source document you can also specify `cover-image`
    in a YAML metadata block (see [EPUB Metadata], below).

`--epub-metadata=`*FILE*

:   Look in the specified XML file for metadata for the EPUB.
    The file should contain a series of [Dublin Core elements].
    For example:

         <dc:rights>Creative Commons</dc:rights>
         <dc:language>es-AR</dc:language>

    By default, pandoc will include the following metadata elements:
    `<dc:title>` (from the document title), `<dc:creator>` (from the
    document authors), `<dc:date>` (from the document date, which should
    be in [ISO 8601 format]), `<dc:language>` (from the `lang`
    variable, or, if is not set, the locale), and `<dc:identifier
    id="BookId">` (a randomly generated UUID). Any of these may be
    overridden by elements in the metadata file.

    Note: if the source document is markdown, a YAML metadata block
    in the document can be used instead.  See below under
    [EPUB Metadata].

`--epub-embed-font=`*FILE*

:   Embed the specified font in the EPUB. This option can be repeated
    to embed multiple fonts.  Wildcards can also be used: for example,
    `DejaVuSans-*.ttf`.  However, if you use wildcards on the command
    line, be sure to escape them or put the whole filename in single quotes,
    to prevent them from being interpreted by the shell. To use the
    embedded fonts, you will need to add declarations like the following
    to your CSS (see `--epub-stylesheet`):

        @font-face {
        font-family: DejaVuSans;
        font-style: normal;
        font-weight: normal;
        src:url("DejaVuSans-Regular.ttf");
        }
        @font-face {
        font-family: DejaVuSans;
        font-style: normal;
        font-weight: bold;
        src:url("DejaVuSans-Bold.ttf");
        }
        @font-face {
        font-family: DejaVuSans;
        font-style: italic;
        font-weight: normal;
        src:url("DejaVuSans-Oblique.ttf");
        }
        @font-face {
        font-family: DejaVuSans;
        font-style: italic;
        font-weight: bold;
        src:url("DejaVuSans-BoldOblique.ttf");
        }
        body { font-family: "DejaVuSans"; }

`--epub-chapter-level=`*NUMBER*

:   Specify the header level at which to split the EPUB into separate
    "chapter" files. The default is to split into chapters at level 1
    headers. This option only affects the internal composition of the
    EPUB, not the way chapters and sections are displayed to users. Some
    readers may be slow if the chapter files are too large, so for large
    documents with few level 1 headers, one might want to use a chapter
    level of 2 or 3.

`--latex-engine=pdflatex`|`lualatex`|`xelatex`

:   Use the specified LaTeX engine when producing PDF output.
    The default is `pdflatex`.  If the engine is not in your PATH,
    the full path of the engine may be specified here.

`--latex-engine-opt=`*STRING*

:   Use the given string as a command-line argument to the `latex-engine`.
    If used multiple times, the arguments are provided with spaces between
    them. Note that no check for duplicate options is done.

[Dublin Core elements]: http://dublincore.org/documents/dces/
[ISO 8601 format]: http://www.w3.org/TR/NOTE-datetime

Citation rendering
------------------

`--bibliography=`*FILE*

:   Set the `bibliography` field in the document's metadata to *FILE*,
    overriding any value set in the metadata, and process citations
    using `pandoc-citeproc`. (This is equivalent to
    `--metadata bibliography=FILE --filter pandoc-citeproc`.)
    If `--natbib` or `--biblatex` is also supplied, `pandoc-citeproc` is not
    used, making this equivalent to `--metadata bibliography=FILE`.
    If you supply this argument multiple times, each *FILE* will be added
    to bibliography.

`--csl=`*FILE*

:   Set the `csl` field in the document's metadata to *FILE*,
    overriding any value set in the metadata.  (This is equivalent to
    `--metadata csl=FILE`.)
    This option is only relevant with `pandoc-citeproc`.

`--citation-abbreviations=`*FILE*

:   Set the `citation-abbreviations` field in the document's metadata to
    *FILE*, overriding any value set in the metadata.  (This is equivalent to
    `--metadata citation-abbreviations=FILE`.)
    This option is only relevant with `pandoc-citeproc`.

`--natbib`

:   Use [`natbib`] for citations in LaTeX output.  This option is not for use
    with the `pandoc-citeproc` filter or with PDF output.  It is intended for
    use in producing a LaTeX file that can be processed with [`bibtex`].

`--biblatex`

:   Use [`biblatex`] for citations in LaTeX output.  This option is not for use
    with the `pandoc-citeproc` filter or with PDF output. It is intended for
    use in producing a LaTeX file that can be processed with [`bibtex`] or [`biber`].

Math rendering in HTML
----------------------

`-m` [*URL*], `--latexmathml`[`=`*URL*]

:   Use the [LaTeXMathML] script to display embedded TeX math in HTML output.
    To insert a link to a local copy of the `LaTeXMathML.js` script,
    provide a *URL*. If no *URL* is provided, the contents of the
    script will be inserted directly into the HTML header, preserving
    portability at the price of efficiency. If you plan to use math on
    several pages, it is much better to link to a copy of the script,
    so it can be cached.

`--mathml`[`=`*URL*]

:   Convert TeX math to [MathML] (in `docbook` as well as `html` and `html5`).
    In standalone `html` output, a small javascript (or a link to such a
    script if a *URL* is supplied) will be inserted that allows the MathML to
    be viewed on some browsers.

`--jsmath`[`=`*URL*]

:   Use [jsMath] to display embedded TeX math in HTML output.
    The *URL* should point to the jsMath load script (e.g.
    `jsMath/easy/load.js`); if provided, it will be linked to in
    the header of standalone HTML documents. If a *URL* is not provided,
    no link to the jsMath load script will be inserted; it is then
    up to the author to provide such a link in the HTML template.

`--mathjax`[`=`*URL*]

:   Use [MathJax] to display embedded TeX math in HTML output.
    The *URL* should point to the `MathJax.js` load script.
    If a *URL* is not provided, a link to the MathJax CDN will
    be inserted.

`--gladtex`

:   Enclose TeX math in `<eq>` tags in HTML output.  These can then
    be processed by [gladTeX] to produce links to images of the typeset
    formulas.

`--mimetex`[`=`*URL*]

:   Render TeX math using the [mimeTeX] CGI script.  If *URL* is not
    specified, it is assumed that the script is at `/cgi-bin/mimetex.cgi`.

`--webtex`[`=`*URL*]

:   Render TeX formulas using an external script that converts TeX
    formulas to images. The formula will be concatenated with the URL
    provided. If *URL* is not specified, the Google Chart API will be used.

`--katex`[`=`*URL*]

:   Use [KaTeX] to display embedded TeX math in HTML output.
    The *URL* should point to the `katex.js` load script. If a *URL* is
    not provided, a link to the KaTeX CDN will be inserted.

`--katex-stylesheet=`*URL*

:   The *URL* should point to the `katex.css` stylesheet. If this option is
    not specified, a link to the KaTeX CDN will be inserted. Note that this
    option does not imply `--katex`.

[MathML]: http://www.w3.org/Math/
[LaTeXMathML]: http://math.etsu.edu/LaTeXMathML/
[jsMath]: http://www.math.union.edu/~dpvc/jsmath/
[MathJax]: https://www.mathjax.org
[gladTeX]: http://ans.hsh.no/home/mgg/gladtex/
[mimeTeX]: http://www.forkosh.com/mimetex.html
[KaTeX]: https://github.com/Khan/KaTeX

Options for wrapper scripts
---------------------------

`--dump-args`

:   Print information about command-line arguments to *stdout*, then exit.
    This option is intended primarily for use in wrapper scripts.
    The first line of output contains the name of the output file specified
    with the `-o` option, or `-` (for *stdout*) if no output file was
    specified.  The remaining lines contain the command-line arguments,
    one per line, in the order they appear.  These do not include regular
    Pandoc options and their arguments, but do include any options appearing
    after a `--` separator at the end of the line.

`--ignore-args`

:   Ignore command-line arguments (for use in wrapper scripts).
    Regular Pandoc options are not ignored.  Thus, for example,

        pandoc --ignore-args -o foo.html -s foo.txt -- -e latin1

    is equivalent to

        pandoc -o foo.html -s

Templates
=========

When the `-s/--standalone` option is used, pandoc uses a template to
add header and footer material that is needed for a self-standing
document.  To see the default template that is used, just type

    pandoc -D *FORMAT*

where *FORMAT* is the name of the output format. A custom template
can be specified using the `--template` option.  You can also override
the system default templates for a given output format *FORMAT*
by putting a file `templates/default.*FORMAT*` in the user data
directory (see `--data-dir`, above). *Exceptions:* For `odt` output,
customize the `default.opendocument` template.  For `pdf` output,
customize the `default.latex` template.

Templates contain *variables*, which allow for the inclusion of
arbitrary information at any point in the file. Variables may be set 
within the document using [YAML metadata blocks][Extension: `yaml_metadata_block`].
They may also be set at the
command line using the `-V/--variable` option: variables set in this
way override metadata fields with the same name.

Variables set by pandoc
-----------------------

Some variables are set automatically by pandoc.  These vary somewhat
depending on the output format, but include metadata fields as well as the following:

`title`, `author`, `date`
:   allow identification of basic aspects of the document.
    Included in PDF metadata through LaTeX.
    These can be set through a [pandoc title block][Extension: `pandoc_title_block`],
    which allows for multiple authors, or through a YAML metadata block:

        ---
        author:
        - Aristotle
        - Peter Abelard
        ...

`abstract`
:   allows for specification of document summary in LaTeX and Word docx

`header-includes`
:   contents specified by `-H/--include-in-header` (may have multiple
    values)

`toc`
:   non-null value if `--toc/--table-of-contents` was specified

`include-before`
:   contents specified by `-B/--include-before-body` (may have
    multiple values)

`include-after`
:   contents specified by `-A/--include-after-body` (may have
    multiple values)

`body`
:   body of document

Language variables
------------------

`lang`
:   identifies the main language of the document,
    using a code according to [BCP 47] (e.g. `en` or `en-GB`).
    For some output formats, pandoc will convert it to an appropriate
    format stored in the additional variables `babel-lang`,
    `polyglossia-lang` (LaTeX) and `context-lang` (ConTeXt).

    Native pandoc `span`s and `div`s with the lang attribute
    (value in BCP 47) can be used to switch the language in
    that range.

`otherlangs`
:   a list of other languages used in the document
    in the YAML metadata, according to [BCP 47]. For example:
    `otherlangs: [en-GB, fr]`.
    This is automatically generated from the `lang` attributes
    in all `span`s and `div`s but can be overriden.
    Currently only used by LaTeX through the generated
    `babel-otherlangs` and `polyglossia-otherlangs` variables.
    The LaTeX writer outputs polyglossia commands in the text but
    the `babel-newcommands` variable contains mappings for them
    to the corresponding babel.

`dir`
:   the base direction of the document, either `rtl` (right-to-left)
    or `ltr` (left-to-right).

    For bidirectional documents, native pandoc `span`s and `div`s
    with the `dir` attribute (value `rtl` or `ltr`) can be used to
    override the base direction in some output formats.
    This may not always be necessary if the final renderer
    (e.g. the browser, when generating HTML) supports the
    [Unicode Bidirectional Algorithm].

    When using LaTeX for bidirectional documents, only the `xelatex` engine
    is fully supported (use `--latex-engine=xelatex`).

[BCP 47]: https://tools.ietf.org/html/bcp47
[Unicode Bidirectional Algorithm]: http://www.w3.org/International/articles/inline-bidi-markup/uba-basics

Variables for slides
--------------------

Variables are available for [producing slide shows with pandoc],
including all [reveal.js configuration options].

`slidy-url`
:   base URL for Slidy documents (defaults to
    `http://www.w3.org/Talks/Tools/Slidy2`)

`slideous-url`
:   base URL for Slideous documents (defaults to `slideous`)

`s5-url`
:   base URL for S5 documents (defaults to `s5/default`)

`revealjs-url`
:   base URL for reveal.js documents (defaults to `reveal.js`)

`theme`, `colortheme`, `fonttheme`, `innertheme`, `outertheme`
:   themes for LaTeX [`beamer`] documents

[reveal.js configuration options]: https://github.com/hakimel/reveal.js#configuration

Variables for LaTeX
-------------------

LaTeX variables are used when [creating a PDF].

`fontsize`
:   font size (e.g. `10pt`, `12pt`) for LaTeX documents

`documentclass`
:   document class for LaTeX documents, e.g. [`article`], [`report`], [`book`], [`memoir`]

`classoption`
:   option for LaTeX document class, e.g. `oneside`; may be repeated
    for multiple options

`geometry`
:   option for LaTeX [`geometry`] package, e.g. `margin=1in`;
    may be repeated for multiple options

`linestretch`
:   adjusts line spacing in LaTeX documents using the [`setspace`]
    package, e.g. `1.25`, `1.5`

`fontfamily`
:   font package for LaTeX documents (with `pdflatex`):
    [TeX Live] includes many options, documented in the [LaTeX Font Catalogue].
    The default is [Latin Modern][`lm`].

`fontfamilyoptions`
:   options for package used as `fontfamily`: e.g. `osf,sc` with
    `fontfamily` set to [`mathpazo`] provides Palatino with old-style
    figures and true small caps

`mainfont`, `sansfont`, `monofont`, `mathfont`, `CJKmainfont`
:   fonts for LaTeX documents (works only with `xelatex` and
    `lualatex`): takes the name of any system font, using the
    [`fontspec`] package.  Note that if `CJKmainfont` is used,
    the [`xecjk`] package must be available.

`mainfontoptions`, `sansfontoptions`, `monofontoptions`, `mathfontoptions`, `CJKoptions`
:   options to use with `mainfont`, `sansfont`, `monofont`, `mathfont`,
    `CJKmainfont` in `xelatex` and `lualatex`.  Allows for any choices
    available through [`fontspec`], such as the OpenType features
    `Numbers=OldStyle,Numbers=Proportional`.

`fontenc`
:   allows font encoding to be specified through `fontenc` package (with `pdflatex`);
    default is `T1` (see guide to [LaTeX font encodings])

`linkcolor`, `toccolor`, `urlcolor`, `citecolor`
:   color for internal links, links in table of contents, external links,
    and citation links in LaTeX documents, using options available through
    [`color`] package, e.g. `red`, `green`, `magenta`, `cyan`, `blue`, `black`

`hidelinks`
:   enables `hidelinks` option for [`hyperref`], disabling link color

`links-as-notes`
:   causes links to be printed as footnotes in LaTeX documents

`indent`
:   uses document class settings for indentation (the default LaTeX template
    otherwise removes indentation and adds space between paragraphs)

`subparagraph`
:   disables default behavior of LaTeX template that redefines (sub)paragraphs
    as sections, changing the appearance of nested headings in some classes

`toc`
:   include table of contents in LaTeX documents

`toc-depth`
:   level of section to include in table of contents in LaTeX documents

`toc-title`
:   title of table of contents (works only with EPUB and docx)

`lof`
:   include list of figures in LaTeX documents

`lot`
:   include list of tables in LaTeX documents

`bibliography`
:   bibliography to use for resolving references

`biblio-style`
:   bibliography style in LaTeX, when used with `--natbib`

[`article`]: https://ctan.org/pkg/article
[`report`]: https://ctan.org/pkg/report
[`book`]: https://ctan.org/pkg/book
[`memoir`]: https://ctan.org/pkg/memoir
[LaTeX Font Catalogue]: http://www.tug.dk/FontCatalogue/
[`mathpazo`]: https://ctan.org/pkg/mathpazo
[LaTeX font encodings]: https://ctan.org/pkg/encguide

Variables for man pages
-----------------------

`section`
:   section number in man pages

`header`
:   header in man pages

`footer`
:   footer in man pages

`adjusting`
:   adjusts text to left (`l`), right (`r`), center (`c`),
    or both (`b`) margins

`hyphenate`
:   if `true` (the default), hyphenation will be used

Using variables in templates
----------------------------

Variable names are sequences of alphanumerics, `-`, and `_`,
starting with a letter.  A variable name surrounded by `$` signs
will be replaced by its value.  For example, the string `$title$` in

    <title>$title$</title>

will be replaced by the document title.

To write a literal `$` in a template, use `$$`.

Templates may contain conditionals.  The syntax is as follows:

    $if(variable)$
    X
    $else$
    Y
    $endif$

This will include `X` in the template if `variable` has a non-null
value; otherwise it will include `Y`. `X` and `Y` are placeholders for
any valid template text, and may include interpolated variables or other
conditionals. The `$else$` section may be omitted.

When variables can have multiple values (for example, `author` in
a multi-author document), you can use the `$for$` keyword:

    $for(author)$
    <meta name="author" content="$author$" />
    $endfor$

You can optionally specify a separator to be used between
consecutive items:

    $for(author)$$author$$sep$, $endfor$

A dot can be used to select a field of a variable that takes
an object as its value.  So, for example:

    $author.name$ ($author.affiliation$)

If you use custom templates, you may need to revise them as pandoc
changes.  We recommend tracking the changes in the default templates,
and modifying your custom templates accordingly. An easy way to do this
is to fork the [pandoc-templates] repository and merge in changes after each
pandoc release.

[pandoc-templates]: https://github.com/jgm/pandoc-templates

Pandoc's markdown
=================

Pandoc understands an extended and slightly revised version of
John Gruber's [markdown] syntax.  This document explains the syntax,
noting differences from standard markdown. Except where noted, these
differences can be suppressed by using the `markdown_strict` format instead
of `markdown`.  An extensions can be enabled by adding `+EXTENSION`
to the format name and disabled by adding `-EXTENSION`. For example,
`markdown_strict+footnotes` is strict markdown with footnotes
enabled, while `markdown-footnotes-pipe_tables` is pandoc's
markdown without footnotes or pipe tables.

Philosophy
----------

Markdown is designed to be easy to write, and, even more importantly,
easy to read:

> A Markdown-formatted document should be publishable as-is, as plain
> text, without looking like it's been marked up with tags or formatting
> instructions.
> -- [John Gruber](http://daringfireball.net/projects/markdown/syntax#philosophy)

This principle has guided pandoc's decisions in finding syntax for
tables, footnotes, and other extensions.

There is, however, one respect in which pandoc's aims are different
from the original aims of markdown.  Whereas markdown was originally
designed with HTML generation in mind, pandoc is designed for multiple
output formats.  Thus, while pandoc allows the embedding of raw HTML,
it discourages it, and provides other, non-HTMLish ways of representing
important document elements like definition lists, tables, mathematics, and
footnotes.

Paragraphs
----------

A paragraph is one or more lines of text followed by one or more blank lines.
Newlines are treated as spaces, so you can reflow your paragraphs as you like.
If you need a hard line break, put two or more spaces at the end of a line.

#### Extension: `escaped_line_breaks` ####

A backslash followed by a newline is also a hard line break.
Note:  in multiline and grid table cells, this is the only way
to create a hard line break, since trailing spaces in the cells
are ignored.

Headers
-------

There are two kinds of headers: Setext and ATX.

### Setext-style headers ###

A setext-style header is a line of text "underlined" with a row of `=` signs
(for a level one header) or `-` signs (for a level two header):

    A level-one header
    ==================

    A level-two header
    ------------------

The header text can contain inline formatting, such as emphasis (see
[Inline formatting], below).


### ATX-style headers ###

An ATX-style header consists of one to six `#` signs and a line of
text, optionally followed by any number of `#` signs.  The number of
`#` signs at the beginning of the line is the header level:

    ## A level-two header

    ### A level-three header ###

As with setext-style headers, the header text can contain formatting:

    # A level-one header with a [link](/url) and *emphasis*

#### Extension: `blank_before_header` ####

Standard markdown syntax does not require a blank line before a header.
Pandoc does require this (except, of course, at the beginning of the
document). The reason for the requirement is that it is all too easy for a
`#` to end up at the beginning of a line by accident (perhaps through line
wrapping). Consider, for example:

    I like several of their flavors of ice cream:
    #22, for example, and #5.


### Header identifiers ###

#### Extension: `header_attributes` ####

Headers can be assigned attributes using this syntax at the end
of the line containing the header text:

    {#identifier .class .class key=value key=value}

Thus, for example, the following headers will all be assigned the identifier
`foo`:

    # My header {#foo}

    ## My header ##    {#foo}

    My other header   {#foo}
    ---------------

(This syntax is compatible with [PHP Markdown Extra].)

Note that although this syntax allows assignment of classes and key/value
attributes, writers generally don't use all of this information.  Identifiers,
classes, and key/value attributes are used in HTML and HTML-based formats such
as EPUB and slidy.  Identifiers are used for labels and link anchors in the
LaTeX, ConTeXt, Textile, and AsciiDoc writers.

Headers with the class `unnumbered` will not be numbered, even if
`--number-sections` is specified.  A single hyphen (`-`) in an attribute
context is equivalent to `.unnumbered`, and preferable in non-English
documents.  So,

    # My header {-}

is just the same as

    # My header {.unnumbered}

#### Extension: `auto_identifiers` ####

A header without an explicitly specified identifier will be
automatically assigned a unique identifier based on the header text.
To derive the identifier from the header text,

  - Remove all formatting, links, etc.
  - Remove all footnotes.
  - Remove all punctuation, except underscores, hyphens, and periods.
  - Replace all spaces and newlines with hyphens.
  - Convert all alphabetic characters to lowercase.
  - Remove everything up to the first letter (identifiers may
    not begin with a number or punctuation mark).
  - If nothing is left after this, use the identifier `section`.

Thus, for example,

  Header                            Identifier
  -------------------------------   ----------------------------
  `Header identifiers in HTML`      `header-identifiers-in-html`
  `*Dogs*?--in *my* house?`         `dogs--in-my-house`
  `[HTML], [S5], or [RTF]?`         `html-s5-or-rtf`
  `3. Applications`                 `applications`
  `33`                              `section`

These rules should, in most cases, allow one to determine the identifier
from the header text. The exception is when several headers have the
same text; in this case, the first will get an identifier as described
above; the second will get the same identifier with `-1` appended; the
third with `-2`; and so on.

These identifiers are used to provide link targets in the table of
contents generated by the `--toc|--table-of-contents` option. They
also make it easy to provide links from one section of a document to
another. A link to this section, for example, might look like this:

    See the section on
    [header identifiers](#header-identifiers-in-html-latex-and-context).

Note, however, that this method of providing links to sections works
only in HTML, LaTeX, and ConTeXt formats.

If the `--section-divs` option is specified, then each section will
be wrapped in a `div` (or a `section`, if `--html5` was specified),
and the identifier will be attached to the enclosing `<div>`
(or `<section>`) tag rather than the header itself. This allows entire
sections to be manipulated using javascript or treated differently in
CSS.

#### Extension: `implicit_header_references` ####

Pandoc behaves as if reference links have been defined for each header.
So, instead of

    [header identifiers](#header-identifiers-in-html)

you can simply write

    [header identifiers]

or

    [header identifiers][]

or

    [the section on header identifiers][header identifiers]

If there are multiple headers with identical text, the corresponding
reference will link to the first one only, and you will need to use explicit
links to link to the others, as described above.

Like regular reference links, these references are case-insensitive.

Explicit link reference definitions always take priority over
implicit header references.  So, in the following example, the
link will point to `bar`, not to `#foo`:

    # Foo

    [foo]: bar

    See [foo]

Block quotations
----------------

Markdown uses email conventions for quoting blocks of text.
A block quotation is one or more paragraphs or other block elements
(such as lists or headers), with each line preceded by a `>` character
and an optional space. (The `>` need not start at the left margin, but
it should not be indented more than three spaces.)

    > This is a block quote. This
    > paragraph has two lines.
    >
    > 1. This is a list inside a block quote.
    > 2. Second item.

A "lazy" form, which requires the `>` character only on the first
line of each block, is also allowed:

    > This is a block quote. This
    paragraph has two lines.

    > 1. This is a list inside a block quote.
    2. Second item.

Among the block elements that can be contained in a block quote are
other block quotes. That is, block quotes can be nested:

    > This is a block quote.
    >
    > > A block quote within a block quote.

If the `>` character is followed by an optional space, that space
will be considered part of the block quote marker and not part of
the indentation of the contents.  Thus, to put an indented code
block in a block quote, you need five spaces after the `>`:

    >     code

#### Extension: `blank_before_blockquote` ####

Standard markdown syntax does not require a blank line before a block
quote.  Pandoc does require this (except, of course, at the beginning of the
document). The reason for the requirement is that it is all too easy for a
`>` to end up at the beginning of a line by accident (perhaps through line
wrapping). So, unless the `markdown_strict` format is used, the following does
not produce a nested block quote in pandoc:

    > This is a block quote.
    >> Nested.


Verbatim (code) blocks
----------------------

### Indented code blocks ###

A block of text indented four spaces (or one tab) is treated as verbatim
text: that is, special characters do not trigger special formatting,
and all spaces and line breaks are preserved.  For example,

        if (a > 3) {
          moveShip(5 * gravity, DOWN);
        }

The initial (four space or one tab) indentation is not considered part
of the verbatim text, and is removed in the output.

Note: blank lines in the verbatim text need not begin with four spaces.


### Fenced code blocks ###

#### Extension: `fenced_code_blocks` ####

In addition to standard indented code blocks, Pandoc supports
*fenced* code blocks.  These begin with a row of three or more
tildes (`~`) and end with a row of tildes that must be at least as long as
the starting row. Everything between these lines is treated as code. No
indentation is necessary:

    ~~~~~~~
    if (a > 3) {
      moveShip(5 * gravity, DOWN);
    }
    ~~~~~~~

Like regular code blocks, fenced code blocks must be separated
from surrounding text by blank lines.

If the code itself contains a row of tildes or backticks, just use a longer
row of tildes or backticks at the start and end:

    ~~~~~~~~~~~~~~~~
    ~~~~~~~~~~
    code including tildes
    ~~~~~~~~~~
    ~~~~~~~~~~~~~~~~

#### Extension: `backtick_code_blocks` ####

Same as `fenced_code_blocks`, but uses backticks (`` ` ``) instead of tildes
(`~`).

#### Extension: `fenced_code_attributes` ####

Optionally, you may attach attributes to fenced or backtick code block using
this syntax:

    ~~~~ {#mycode .haskell .numberLines startFrom="100"}
    qsort []     = []
    qsort (x:xs) = qsort (filter (< x) xs) ++ [x] ++
                   qsort (filter (>= x) xs)
    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Here `mycode` is an identifier, `haskell` and `numberLines` are classes, and
`startFrom` is an attribute with value `100`. Some output formats can use this
information to do syntax highlighting. Currently, the only output formats
that uses this information are HTML and LaTeX. If highlighting is supported
for your output format and language, then the code block above will appear
highlighted, with numbered lines. (To see which languages are supported, do
`pandoc --version`.) Otherwise, the code block above will appear as follows:

    <pre id="mycode" class="haskell numberLines" startFrom="100">
      <code>
      ...
      </code>
    </pre>

A shortcut form can also be used for specifying the language of
the code block:

    ```haskell
    qsort [] = []
    ```

This is equivalent to:

    ``` {.haskell}
    qsort [] = []
    ```

If the `fenced_code_attributes` extension is disabled, but
input contains class attribute(s) for the codeblock, the first
class attribute will be printed after the opening fence as a bare
word.

To prevent all highlighting, use the `--no-highlight` flag.
To set the highlighting style, use `--highlight-style`.
For more information on highlighting, see [Syntax highlighting],
below.

Line blocks
-----------

#### Extension: `line_blocks` ####

A line block is a sequence of lines beginning with a vertical bar (`|`)
followed by a space.  The division into lines will be preserved in
the output, as will any leading spaces; otherwise, the lines will
be formatted as markdown.  This is useful for verse and addresses:

    | The limerick packs laughs anatomical
    | In space that is quite economical.
    |    But the good ones I've seen
    |    So seldom are clean
    | And the clean ones so seldom are comical

    | 200 Main St.
    | Berkeley, CA 94718

The lines can be hard-wrapped if needed, but the continuation
line must begin with a space.

    | The Right Honorable Most Venerable and Righteous Samuel L.
      Constable, Jr.
    | 200 Main St.
    | Berkeley, CA 94718

This syntax is borrowed from [reStructuredText].

Lists
-----

### Bullet lists ###

A bullet list is a list of bulleted list items.  A bulleted list
item begins with a bullet (`*`, `+`, or `-`).  Here is a simple
example:

    * one
    * two
    * three

This will produce a "compact" list. If you want a "loose" list, in which
each item is formatted as a paragraph, put spaces between the items:

    * one

    * two

    * three

The bullets need not be flush with the left margin; they may be
indented one, two, or three spaces. The bullet must be followed
by whitespace.

List items look best if subsequent lines are flush with the first
line (after the bullet):

    * here is my first
      list item.
    * and my second.

But markdown also allows a "lazy" format:

    * here is my first
    list item.
    * and my second.

### The four-space rule ###

A list item may contain multiple paragraphs and other block-level
content. However, subsequent paragraphs must be preceded by a blank line
and indented four spaces or a tab. The list will look better if the first
paragraph is aligned with the rest:

      * First paragraph.

        Continued.

      * Second paragraph. With a code block, which must be indented
        eight spaces:

            { code }

List items may include other lists.  In this case the preceding blank
line is optional.  The nested list must be indented four spaces or
one tab:

    * fruits
        + apples
            - macintosh
            - red delicious
        + pears
        + peaches
    * vegetables
        + broccoli
        + chard

As noted above, markdown allows you to write list items "lazily," instead of
indenting continuation lines. However, if there are multiple paragraphs or
other blocks in a list item, the first line of each must be indented.

    + A lazy, lazy, list
    item.

    + Another one; this looks
    bad but is legal.

        Second paragraph of second
    list item.

**Note:**  Although the four-space rule for continuation paragraphs
comes from the official [markdown syntax guide], the reference implementation,
`Markdown.pl`, does not follow it. So pandoc will give different results than
`Markdown.pl` when authors have indented continuation paragraphs fewer than
four spaces.

The [markdown syntax guide] is not explicit whether the four-space
rule applies to *all* block-level content in a list item; it only
mentions paragraphs and code blocks.  But it implies that the rule
applies to all block-level content (including nested lists), and
pandoc interprets it that way.

  [markdown syntax guide]:
    http://daringfireball.net/projects/markdown/syntax#list

### Ordered lists ###

Ordered lists work just like bulleted lists, except that the items
begin with enumerators rather than bullets.

In standard markdown, enumerators are decimal numbers followed
by a period and a space.  The numbers themselves are ignored, so
there is no difference between this list:

    1.  one
    2.  two
    3.  three

and this one:

    5.  one
    7.  two
    1.  three

#### Extension: `fancy_lists` ####

Unlike standard markdown, Pandoc allows ordered list items to be marked
with uppercase and lowercase letters and roman numerals, in addition to
arabic numerals. List markers may be enclosed in parentheses or followed by a
single right-parentheses or period. They must be separated from the
text that follows by at least one space, and, if the list marker is a
capital letter with a period, by at least two spaces.[^2]

[^2]:  The point of this rule is to ensure that normal paragraphs
    starting with people's initials, like

        B. Russell was an English philosopher.

    do not get treated as list items.

    This rule will not prevent

        (C) 2007 Joe Smith

    from being interpreted as a list item.  In this case, a backslash
    escape can be used:

        (C\) 2007 Joe Smith

The `fancy_lists` extension also allows '`#`' to be used as an
ordered list marker in place of a numeral:

    #. one
    #. two

#### Extension: `startnum` ####

Pandoc also pays attention to the type of list marker used, and to the
starting number, and both of these are preserved where possible in the
output format. Thus, the following yields a list with numbers followed
by a single parenthesis, starting with 9, and a sublist with lowercase
roman numerals:

     9)  Ninth
    10)  Tenth
    11)  Eleventh
           i. subone
          ii. subtwo
         iii. subthree

Pandoc will start a new list each time a different type of list
marker is used.  So, the following will create three lists:

    (2) Two
    (5) Three
    1.  Four
    *   Five

If default list markers are desired, use `#.`:

    #.  one
    #.  two
    #.  three


### Definition lists ###

#### Extension: `definition_lists` ####

Pandoc supports definition lists, using the syntax of
[PHP Markdown Extra] with some extensions.[^3]

    Term 1

    :   Definition 1

    Term 2 with *inline markup*

    :   Definition 2

            { some code, part of Definition 2 }

        Third paragraph of definition 2.

Each term must fit on one line, which may optionally be followed by
a blank line, and must be followed by one or more definitions.
A definition begins with a colon or tilde, which may be indented one
or two spaces.

A term may have multiple definitions, and each definition may consist of one or
more block elements (paragraph, code block, list, etc.), each indented four
spaces or one tab stop.  The body of the definition (including the first line,
aside from the colon or tilde) should be indented four spaces. However,
as with other markdown lists, you can "lazily" omit indentation except
at the beginning of a paragraph or other block element:

    Term 1

    :   Definition
    with lazy continuation.

        Second paragraph of the definition.

If you leave space before the definition (as in the example above),
the text of the definition will be treated as a paragraph.  In some
output formats, this will mean greater spacing between term/definition
pairs. For a more compact definition list, omit the space before the
definition:

    Term 1
      ~ Definition 1

    Term 2
      ~ Definition 2a
      ~ Definition 2b

Note that space between items in a definition list is required.
(A variant that loosens this requirement, but disallows "lazy"
hard wrapping, can be activated with `compact_definition_lists`: see
[Non-pandoc extensions], below.)

[^3]:  I have been influenced by the suggestions of [David Wheeler](http://www.justatheory.com/computers/markup/modest-markdown-proposal.html).

### Numbered example lists ###

#### Extension: `example_lists` ####

The special list marker `@` can be used for sequentially numbered
examples. The first list item with a `@` marker will be numbered '1',
the next '2', and so on, throughout the document. The numbered examples
need not occur in a single list; each new list using `@` will take up
where the last stopped. So, for example:

    (@)  My first example will be numbered (1).
    (@)  My second example will be numbered (2).

    Explanation of examples.

    (@)  My third example will be numbered (3).

Numbered examples can be labeled and referred to elsewhere in the
document:

    (@good)  This is a good example.

    As (@good) illustrates, ...

The label can be any string of alphanumeric characters, underscores,
or hyphens.


### Compact and loose lists ###

Pandoc behaves differently from `Markdown.pl` on some "edge
cases" involving lists.  Consider this source:

    +   First
    +   Second:
    	-   Fee
    	-   Fie
    	-   Foe

    +   Third

Pandoc transforms this into a "compact list" (with no `<p>` tags around
"First", "Second", or "Third"), while markdown puts `<p>` tags around
"Second" and "Third" (but not "First"), because of the blank space
around "Third". Pandoc follows a simple rule: if the text is followed by
a blank line, it is treated as a paragraph. Since "Second" is followed
by a list, and not a blank line, it isn't treated as a paragraph. The
fact that the list is followed by a blank line is irrelevant. (Note:
Pandoc works this way even when the `markdown_strict` format is specified. This
behavior is consistent with the official markdown syntax description,
even though it is different from that of `Markdown.pl`.)


### Ending a list ###

What if you want to put an indented code block after a list?

    -   item one
    -   item two

        { my code block }

Trouble! Here pandoc (like other markdown implementations) will treat
`{ my code block }` as the second paragraph of item two, and not as
a code block.

To "cut off" the list after item two, you can insert some non-indented
content, like an HTML comment, which won't produce visible output in
any format:

    -   item one
    -   item two

    <!-- end of list -->

        { my code block }

You can use the same trick if you want two consecutive lists instead
of one big list:

    1.  one
    2.  two
    3.  three

    <!-- -->

    1.  uno
    2.  dos
    3.  tres

Horizontal rules
----------------

A line containing a row of three or more `*`, `-`, or `_` characters
(optionally separated by spaces) produces a horizontal rule:

    *  *  *  *

    ---------------


Tables
------

Four kinds of tables may be used. The first three kinds presuppose the use of
a fixed-width font, such as Courier. The fourth kind can be used with
proportionally spaced fonts, as it does not require lining up columns.

#### Extension: `table_captions` ####

A caption may optionally be provided with all 4 kinds of tables (as
illustrated in the examples below). A caption is a paragraph beginning
with the string `Table:` (or just `:`), which will be stripped off.
It may appear either before or after the table.

#### Extension: `simple_tables` ####

Simple tables look like this:

      Right     Left     Center     Default
    -------     ------ ----------   -------
         12     12        12            12
        123     123       123          123
          1     1          1             1

    Table:  Demonstration of simple table syntax.

The headers and table rows must each fit on one line.  Column
alignments are determined by the position of the header text relative
to the dashed line below it:[^4]

  - If the dashed line is flush with the header text on the right side
    but extends beyond it on the left, the column is right-aligned.
  - If the dashed line is flush with the header text on the left side
    but extends beyond it on the right, the column is left-aligned.
  - If the dashed line extends beyond the header text on both sides,
    the column is centered.
  - If the dashed line is flush with the header text on both sides,
    the default alignment is used (in most cases, this will be left).

[^4]:  This scheme is due to Michel Fortin, who proposed it on the
       [Markdown discussion list](http://six.pairlist.net/pipermail/markdown-discuss/2005-March/001097.html).

The table must end with a blank line, or a line of dashes followed by
a blank line.

The column headers may be omitted, provided a dashed line is used
to end the table. For example:

    -------     ------ ----------   -------
         12     12        12             12
        123     123       123           123
          1     1          1              1
    -------     ------ ----------   -------

When headers are omitted, column alignments are determined on the basis
of the first line of the table body. So, in the tables above, the columns
would be right, left, center, and right aligned, respectively.

#### Extension: `multiline_tables` ####

Multiline tables allow headers and table rows to span multiple lines
of text (but cells that span multiple columns or rows of the table are
not supported).  Here is an example:

    -------------------------------------------------------------
     Centered   Default           Right Left
      Header    Aligned         Aligned Aligned
    ----------- ------- --------------- -------------------------
       First    row                12.0 Example of a row that
                                        spans multiple lines.

      Second    row                 5.0 Here's another one. Note
                                        the blank line between
                                        rows.
    -------------------------------------------------------------

    Table: Here's the caption. It, too, may span
    multiple lines.

These work like simple tables, but with the following differences:

  - They must begin with a row of dashes, before the header text
    (unless the headers are omitted).
  - They must end with a row of dashes, then a blank line.
  - The rows must be separated by blank lines.

In multiline tables, the table parser pays attention to the widths of
the columns, and the writers try to reproduce these relative widths in
the output. So, if you find that one of the columns is too narrow in the
output, try widening it in the markdown source.

Headers may be omitted in multiline tables as well as simple tables:

    ----------- ------- --------------- -------------------------
       First    row                12.0 Example of a row that
                                        spans multiple lines.

      Second    row                 5.0 Here's another one. Note
                                        the blank line between
                                        rows.
    ----------- ------- --------------- -------------------------

    : Here's a multiline table without headers.

It is possible for a multiline table to have just one row, but the row
should be followed by a blank line (and then the row of dashes that ends
the table), or the table may be interpreted as a simple table.

#### Extension: `grid_tables` ####

Grid tables look like this:

    : Sample grid table.

    +---------------+---------------+--------------------+
    | Fruit         | Price         | Advantages         |
    +===============+===============+====================+
    | Bananas       | $1.34         | - built-in wrapper |
    |               |               | - bright color     |
    +---------------+---------------+--------------------+
    | Oranges       | $2.10         | - cures scurvy     |
    |               |               | - tasty            |
    +---------------+---------------+--------------------+

The row of `=`s separates the header from the table body, and can be
omitted for a headerless table. The cells of grid tables may contain
arbitrary block elements (multiple paragraphs, code blocks, lists,
etc.). Alignments are not supported, nor are cells that span multiple
columns or rows. Grid tables can be created easily using [Emacs table mode].

[Emacs table mode]: http://table.sourceforge.net/

#### Extension: `pipe_tables` ####

Pipe tables look like this:

    | Right | Left | Default | Center |
    |------:|:-----|---------|:------:|
    |   12  |  12  |    12   |    12  |
    |  123  |  123 |   123   |   123  |
    |    1  |    1 |     1   |     1  |

      : Demonstration of pipe table syntax.

The syntax is identical to [PHP Markdown Extra tables].  The beginning and
ending pipe characters are optional, but pipes are required between all
columns.  The colons indicate column alignment as shown.  The header
cannot be omitted.  To simulate a headerless table, include a header
with blank cells.

Since the pipes indicate column boundaries, columns need not be vertically
aligned, as they are in the above example.  So, this is a perfectly
legal (though ugly) pipe table:

    fruit| price
    -----|-----:
    apple|2.05
    pear|1.37
    orange|3.09

The cells of pipe tables cannot contain block elements like paragraphs
and lists, and cannot span multiple lines.  Note also that in LaTeX/PDF
output, the cells produced by pipe tables will not wrap, since there
is no information available about relative widths.  If you want content
to wrap within cells, use multiline or grid tables.

Note:  Pandoc also recognizes pipe tables of the following
form, as can be produced by Emacs' orgtbl-mode:

    | One | Two   |
    |-----+-------|
    | my  | table |
    | is  | nice  |

The difference is that `+` is used instead of `|`. Other orgtbl features
are not supported. In particular, to get non-default column alignment,
you'll need to add colons as above.

[PHP Markdown Extra tables]: https://michelf.ca/projects/php-markdown/extra/#table

Metadata blocks
---------------

#### Extension: `pandoc_title_block` ####

If the file begins with a title block

    % title
    % author(s) (separated by semicolons)
    % date

it will be parsed as bibliographic information, not regular text.  (It
will be used, for example, in the title of standalone LaTeX or HTML
output.)  The block may contain just a title, a title and an author,
or all three elements. If you want to include an author but no
title, or a title and a date but no author, you need a blank line:

    %
    % Author

    % My title
    %
    % June 15, 2006

The title may occupy multiple lines, but continuation lines must
begin with leading space, thus:

    % My title
      on multiple lines

If a document has multiple authors, the authors may be put on
separate lines with leading space, or separated by semicolons, or
both.  So, all of the following are equivalent:

    % Author One
      Author Two

    % Author One; Author Two

    % Author One;
      Author Two

The date must fit on one line.

All three metadata fields may contain standard inline formatting
(italics, links, footnotes, etc.).

Title blocks will always be parsed, but they will affect the output only
when the `--standalone` (`-s`) option is chosen. In HTML output, titles
will appear twice: once in the document head -- this is the title that
will appear at the top of the window in a browser -- and once at the
beginning of the document body. The title in the document head can have
an optional prefix attached (`--title-prefix` or `-T` option). The title
in the body appears as an H1 element with class "title", so it can be
suppressed or reformatted with CSS. If a title prefix is specified with
`-T` and no title block appears in the document, the title prefix will
be used by itself as the HTML title.

The man page writer extracts a title, man page section number, and
other header and footer information from the title line. The title
is assumed to be the first word on the title line, which may optionally
end with a (single-digit) section number in parentheses. (There should
be no space between the title and the parentheses.)  Anything after
this is assumed to be additional footer and header text. A single pipe
character (`|`) should be used to separate the footer text from the header
text.  Thus,

    % PANDOC(1)

will yield a man page with the title `PANDOC` and section 1.

    % PANDOC(1) Pandoc User Manuals

will also have "Pandoc User Manuals" in the footer.

    % PANDOC(1) Pandoc User Manuals | Version 4.0

will also have "Version 4.0" in the header.

#### Extension: `yaml_metadata_block` ####

A YAML metadata block is a valid YAML object, delimited by a line of three
hyphens (`---`) at the top and a line of three hyphens (`---`) or three dots
(`...`) at the bottom.  A YAML metadata block may occur anywhere in the
document, but if it is not at the beginning, it must be preceded by a blank
line.  (Note that, because of the way pandoc concatenates input files when
several are provided, you may also keep the metadata in a separate YAML file
and pass it to pandoc as an argument, along with your markdown files:

    pandoc chap1.md chap2.md chap3.md metadata.yaml -s -o book.html

Just be sure that the YAML file begins with `---` and ends with `---` or
`...`.)

Metadata will be taken from the fields of the YAML object and added to any
existing document metadata.  Metadata can contain lists and objects (nested
arbitrarily), but all string scalars will be interpreted as markdown.  Fields
with names ending in an underscore will be ignored by pandoc.  (They may be
given a role by external processors.)

A document may contain multiple metadata blocks.  The metadata fields will
be combined through a *left-biased union*:  if two metadata blocks attempt
to set the same field, the value from the first block will be taken.

When pandoc is used with `-t markdown` to create a markdown document,
a YAML metadata block will be produced only if the `-s/--standalone`
option is used.  All of the metadata will appear in a single block
at the beginning of the document.

Note that YAML escaping rules must be followed. Thus, for example,
if a title contains a colon, it must be quoted.  The pipe character
(`|`) can be used to begin an indented block that will be interpreted
literally, without need for escaping.  This form is necessary
when the field contains blank lines:

    ---
    title:  'This is the title: it contains a colon'
    author:
    - name: Author One
      affiliation: University of Somewhere
    - name: Author Two
      affiliation: University of Nowhere
    tags: [nothing, nothingness]
    abstract: |
      This is the abstract.

      It consists of two paragraphs.
    ...

Template variables will be set automatically from the metadata.  Thus, for
example, in writing HTML, the variable `abstract` will be set to the HTML
equivalent of the markdown in the `abstract` field:

    <p>This is the abstract.</p>
    <p>It consists of two paragraphs.</p>

Note: The `author` variable in the default templates expects a simple list or
string.  To use the structured authors in the example, you would need a
custom template.  For example:

    $for(author)$
    $if(author.name)$
    $author.name$$if(author.affiliation)$ ($author.affiliation$)$endif$
    $else$
    $author$
    $endif$
    $endfor$


Backslash escapes
-----------------

#### Extension: `all_symbols_escapable` ####

Except inside a code block or inline code, any punctuation or space
character preceded by a backslash will be treated literally, even if it
would normally indicate formatting.  Thus, for example, if one writes

    *\*hello\**

one will get

    <em>*hello*</em>

instead of

    <strong>hello</strong>

This rule is easier to remember than standard markdown's rule,
which allows only the following characters to be backslash-escaped:

    \`*_{}[]()>#+-.!

(However, if the `markdown_strict` format is used, the standard markdown rule
will be used.)

A backslash-escaped space is parsed as a nonbreaking space.  It will
appear in TeX output as `~` and in HTML and XML as `\&#160;` or
`\&nbsp;`.

A backslash-escaped newline (i.e. a backslash occurring at the end of
a line) is parsed as a hard line break.  It will appear in TeX output as
`\\` and in HTML as `<br />`.  This is a nice alternative to
markdown's "invisible" way of indicating hard line breaks using
two trailing spaces on a line.

Backslash escapes do not work in verbatim contexts.

Smart punctuation
-----------------

#### Extension ####

If the `--smart` option is specified, pandoc will produce typographically
correct output, converting straight quotes to curly quotes, `---` to
em-dashes, `--` to en-dashes, and `...` to ellipses. Nonbreaking spaces
are inserted after certain abbreviations, such as "Mr."

Note:  if your LaTeX template calls for the [`csquotes`] package, pandoc will
detect this automatically and use `\enquote{...}` for quoted text.

Inline formatting
-----------------

### Emphasis ###

To *emphasize* some text, surround it with `*`s or `_`, like this:

    This text is _emphasized with underscores_, and this
    is *emphasized with asterisks*.

Double `*` or `_` produces **strong emphasis**:

    This is **strong emphasis** and __with underscores__.

A `*` or `_` character surrounded by spaces, or backslash-escaped,
will not trigger emphasis:

    This is * not emphasized *, and \*neither is this\*.

#### Extension: `intraword_underscores` ####

Because `_` is sometimes used inside words and identifiers,
pandoc does not interpret a `_` surrounded by alphanumeric
characters as an emphasis marker.  If you want to emphasize
just part of a word, use `*`:

    feas*ible*, not feas*able*.


### Strikeout ###

#### Extension: `strikeout` ####

To strikeout a section of text with a horizontal line, begin and end it
with `~~`. Thus, for example,

    This ~~is deleted text.~~


### Superscripts and subscripts ###

#### Extension: `superscript`, `subscript` ####

Superscripts may be written by surrounding the superscripted text by `^`
characters; subscripts may be written by surrounding the subscripted
text by `~` characters.  Thus, for example,

    H~2~O is a liquid.  2^10^ is 1024.

If the superscripted or subscripted text contains spaces, these spaces
must be escaped with backslashes.  (This is to prevent accidental
superscripting and subscripting through the ordinary use of `~` and `^`.)
Thus, if you want the letter P with 'a cat' in subscripts, use
`P~a\ cat~`, not `P~a cat~`.


### Verbatim ###

To make a short span of text verbatim, put it inside backticks:

    What is the difference between `>>=` and `>>`?

If the verbatim text includes a backtick, use double backticks:

    Here is a literal backtick `` ` ``.

(The spaces after the opening backticks and before the closing
backticks will be ignored.)

The general rule is that a verbatim span starts with a string
of consecutive backticks (optionally followed by a space)
and ends with a string of the same number of backticks (optionally
preceded by a space).

Note that backslash-escapes (and other markdown constructs) do not
work in verbatim contexts:

    This is a backslash followed by an asterisk: `\*`.

#### Extension: `inline_code_attributes` ####

Attributes can be attached to verbatim text, just as with
[fenced code blocks]:

    `<$>`{.haskell}

### Small caps ###

To write small caps, you can use an HTML span tag:

    <span style="font-variant:small-caps;">Small caps</span>

(The semicolon is optional and there may be space after the
colon.) This will work in all output formats that support small caps.

Math
----

#### Extension: `tex_math_dollars` ####

Anything between two `$` characters will be treated as TeX math.  The
opening `$` must have a non-space character immediately to its right,
while the closing `$` must have a non-space character immediately to its
left, and must not be followed immediately by a digit.  Thus,
`$20,000 and $30,000` won't parse as math.  If for some reason
you need to enclose text in literal `$` characters, backslash-escape
them and they won't be treated as math delimiters.

TeX math will be printed in all output formats. How it is rendered
depends on the output format:

Markdown, LaTeX, Emacs Org mode, ConTeXt
  ~ It will appear verbatim between `$` characters.

reStructuredText
  ~ It will be rendered using an [interpreted text role `:math:`].

AsciiDoc
  ~ It will be rendered as `latexmath:[...]`.

Texinfo
  ~ It will be rendered inside a `@math` command.

groff man
  ~ It will be rendered verbatim without `$`'s.

MediaWiki, DokuWiki
  ~ It will be rendered inside `<math>` tags.

Textile
  ~ It will be rendered inside `<span class="math">` tags.

RTF, OpenDocument, ODT
  ~ It will be rendered, if possible, using unicode characters,
    and will otherwise appear verbatim.

DocBook
  ~ If the `--mathml` flag is used, it will be rendered using MathML
    in an `inlineequation` or `informalequation` tag.  Otherwise it
    will be rendered, if possible, using unicode characters.

Docx
  ~ It will be rendered using OMML math markup.

FictionBook2
  ~ If the `--webtex` option is used, formulas are rendered as images
    using Google Charts or other compatible web service, downloaded
    and embedded in the e-book. Otherwise, they will appear verbatim.

HTML, Slidy, DZSlides, S5, EPUB
  ~ The way math is rendered in HTML will depend on the
    command-line options selected:

    1.  The default is to render TeX math as far as possible using unicode
        characters, as with RTF, DocBook, and OpenDocument output. Formulas
        are put inside a `span` with `class="math"`, so that they may be
        styled differently from the surrounding text if needed.

    2.  If the `--latexmathml` option is used, TeX math will be displayed
        between `$` or `$$` characters and put in `<span>` tags with class `LaTeX`.
        The [LaTeXMathML] script will be used to render it as formulas.
        (This trick does not work in all browsers, but it works in Firefox.
        In browsers that do not support LaTeXMathML, TeX math will appear
        verbatim between `$` characters.)

    3.  If the `--jsmath` option is used, TeX math will be put inside
        `<span>` tags (for inline math) or `<div>` tags (for display math)
        with class `math`.  The [jsMath] script will be used to render
        it.

    4.  If the `--mimetex` option is used, the [mimeTeX] CGI script will
        be called to generate images for each TeX formula. This should
        work in all browsers. The `--mimetex` option takes an optional URL
        as argument. If no URL is specified, it will be assumed that the
        mimeTeX CGI script is at `/cgi-bin/mimetex.cgi`.

    5.  If the `--gladtex` option is used, TeX formulas will be enclosed
        in `<eq>` tags in the HTML output.  The resulting `htex` file may then
        be processed by [gladTeX], which will produce image files for each
        formula and an HTML file with links to these images.  So, the
        procedure is:

            pandoc -s --gladtex myfile.txt -o myfile.htex
            gladtex -d myfile-images myfile.htex
            # produces myfile.html and images in myfile-images

    6.  If the `--webtex` option is used, TeX formulas will be converted
        to `<img>` tags that link to an external script that converts
        formulas to images. The formula will be URL-encoded and concatenated
        with the URL provided. If no URL is specified, the Google Chart
        API will be used (`http://chart.apis.google.com/chart?cht=tx&chl=`).

    7.  If the `--mathjax` option is used, TeX math will be displayed
        between `\(...\)` (for inline math) or `\[...\]` (for display
        math) and put in `<span>` tags with class `math`.
        The [MathJax] script will be used to render it as formulas.

[interpreted text role `:math:`]: http://docutils.sourceforge.net/docs/ref/rst/roles.html#math

Raw HTML
--------

#### Extension: `raw_html` ####

Markdown allows you to insert raw HTML (or DocBook) anywhere in a document
(except verbatim contexts, where `<`, `>`, and `&` are interpreted
literally).  (Technically this is not an extension, since standard
markdown allows it, but it has been made an extension so that it can
be disabled if desired.)

The raw HTML is passed through unchanged in HTML, S5, Slidy, Slideous,
DZSlides, EPUB, Markdown, and Textile output, and suppressed in other
formats.

#### Extension: `markdown_in_html_blocks` ####

Standard markdown allows you to include HTML "blocks":  blocks
of HTML between balanced tags that are separated from the surrounding text
with blank lines, and start and end at the left margin.  Within
these blocks, everything is interpreted as HTML, not markdown;
so (for example), `*` does not signify emphasis.

Pandoc behaves this way when the `markdown_strict` format is used; but
by default, pandoc interprets material between HTML block tags as markdown.
Thus, for example, Pandoc will turn

    <table>
    <tr>
    <td>*one*</td>
    <td>[a link](http://google.com)</td>
    </tr>
    </table>

into

    <table>
    <tr>
    <td><em>one</em></td>
    <td><a href="http://google.com">a link</a></td>
    </tr>
    </table>

whereas `Markdown.pl` will preserve it as is.

There is one exception to this rule:  text between `<script>` and
`<style>` tags is not interpreted as markdown.

This departure from standard markdown should make it easier to mix
markdown with HTML block elements.  For example, one can surround
a block of markdown text with `<div>` tags without preventing it
from being interpreted as markdown.

#### Extension: `native_divs` ####

Use native pandoc `Div` blocks for content inside `<div>` tags.
For the most part this should give the same output as
`markdown_in_html_blocks`, but it makes it easier to write pandoc
filters to manipulate groups of blocks.

#### Extension: `native_spans` ####

Use native pandoc `Span` blocks for content inside `<span>` tags.
For the most part this should give the same output as `raw_html`,
but it makes it easier to write pandoc filters to manipulate groups
of inlines.

Raw TeX
-------

#### Extension: `raw_tex` ####

In addition to raw HTML, pandoc allows raw LaTeX, TeX, and ConTeXt to be
included in a document. Inline TeX commands will be preserved and passed
unchanged to the LaTeX and ConTeXt writers. Thus, for example, you can use
LaTeX to include BibTeX citations:

    This result was proved in \cite{jones.1967}.

Note that in LaTeX environments, like

    \begin{tabular}{|l|l|}\hline
    Age & Frequency \\ \hline
    18--25  & 15 \\
    26--35  & 33 \\
    36--45  & 22 \\ \hline
    \end{tabular}

the material between the begin and end tags will be interpreted as raw
LaTeX, not as markdown.

Inline LaTeX is ignored in output formats other than Markdown, LaTeX,
and ConTeXt.

LaTeX macros
------------

#### Extension: `latex_macros` ####

For output formats other than LaTeX, pandoc will parse LaTeX `\newcommand` and
`\renewcommand` definitions and apply the resulting macros to all LaTeX
math.  So, for example, the following will work in all output formats,
not just LaTeX:

    \newcommand{\tuple}[1]{\langle #1 \rangle}

    $\tuple{a, b, c}$

In LaTeX output, the `\newcommand` definition will simply be passed
unchanged to the output.


Links
-----

Markdown allows links to be specified in several ways.

### Automatic links ###

If you enclose a URL or email address in pointy brackets, it
will become a link:

    <http://google.com>
    <sam@green.eggs.ham>

### Inline links ###

An inline link consists of the link text in square brackets,
followed by the URL in parentheses. (Optionally, the URL can
be followed by a link title, in quotes.)

    This is an [inline link](/url), and here's [one with
    a title](http://fsf.org "click here for a good time!").

There can be no space between the bracketed part and the parenthesized part.
The link text can contain formatting (such as emphasis), but the title cannot.

Email addresses in inline links are not autodetected, so they have to be
prefixed with `mailto`:

    [Write me!](mailto:sam@green.eggs.ham)

### Reference links ###

An *explicit* reference link has two parts, the link itself and the link
definition, which may occur elsewhere in the document (either
before or after the link).

The link consists of link text in square brackets, followed by a label in
square brackets. (There can be space between the two.) The link definition
consists of the bracketed label, followed by a colon and a space, followed by
the URL, and optionally (after a space) a link title either in quotes or in
parentheses.  The label must not be parseable as a citation (assuming
the `citations` extension is enabled):  citations take precedence over
link labels.

Here are some examples:

    [my label 1]: /foo/bar.html  "My title, optional"
    [my label 2]: /foo
    [my label 3]: http://fsf.org (The free software foundation)
    [my label 4]: /bar#special  'A title in single quotes'

The URL may optionally be surrounded by angle brackets:

    [my label 5]: <http://foo.bar.baz>

The title may go on the next line:

    [my label 3]: http://fsf.org
      "The free software foundation"

Note that link labels are not case sensitive.  So, this will work:

    Here is [my link][FOO]

    [Foo]: /bar/baz

In an *implicit* reference link, the second pair of brackets is
empty:

    See [my website][].

    [my website]: http://foo.bar.baz

Note:  In `Markdown.pl` and most other markdown implementations,
reference link definitions cannot occur in nested constructions
such as list items or block quotes.  Pandoc lifts this arbitrary
seeming restriction.  So the following is fine in pandoc, though
not in most other implementations:

    > My block [quote].
    >
    > [quote]: /foo

#### Extension: `shortcut_reference_links` ####

In a *shortcut* reference link, the second pair of brackets may
be omitted entirely:

    See [my website].

    [my website]: http://foo.bar.baz

### Internal links ###

To link to another section of the same document, use the automatically
generated identifier (see [Header identifiers]). For example:

    See the [Introduction](#introduction).

or

    See the [Introduction].

    [Introduction]: #introduction

Internal links are currently supported for HTML formats (including
HTML slide shows and EPUB), LaTeX, and ConTeXt.

Images
------

A link immediately preceded by a `!` will be treated as an image.
The link text will be used as the image's alt text:

    ![la lune](lalune.jpg "Voyage to the moon")

    ![movie reel]

    [movie reel]: movie.gif

#### Extension: `implicit_figures` ####

An image occurring by itself in a paragraph will be rendered as
a figure with a caption.[^5] (In LaTeX, a figure environment will be
used; in HTML, the image will be placed in a `div` with class
`figure`, together with a caption in a `p` with class `caption`.)
The image's alt text will be used as the caption.

    ![This is the caption](/url/of/image.png)

[^5]: This feature is not yet implemented for RTF, OpenDocument, or
    ODT. In those formats, you'll just get an image in a paragraph by
    itself, with no caption.

If you just want a regular inline image, just make sure it is not
the only thing in the paragraph. One way to do this is to insert a
nonbreaking space after the image:

    ![This image won't be a figure](/url/of/image.png)\ 


Footnotes
---------

#### Extension: `footnotes` ####

Pandoc's markdown allows footnotes, using the following syntax:

    Here is a footnote reference,[^1] and another.[^longnote]

    [^1]: Here is the footnote.

    [^longnote]: Here's one with multiple blocks.

        Subsequent paragraphs are indented to show that they
    belong to the previous footnote.

            { some.code }

        The whole paragraph can be indented, or just the first
        line.  In this way, multi-paragraph footnotes work like
        multi-paragraph list items.

    This paragraph won't be part of the note, because it
    isn't indented.

The identifiers in footnote references may not contain spaces, tabs,
or newlines.  These identifiers are used only to correlate the
footnote reference with the note itself; in the output, footnotes
will be numbered sequentially.

The footnotes themselves need not be placed at the end of the
document.  They may appear anywhere except inside other block elements
(lists, block quotes, tables, etc.).

#### Extension: `inline_notes` ####

Inline footnotes are also allowed (though, unlike regular notes,
they cannot contain multiple paragraphs).  The syntax is as follows:

    Here is an inline note.^[Inlines notes are easier to write, since
    you don't have to pick an identifier and move down to type the
    note.]

Inline and regular footnotes may be mixed freely.


Citations
---------

#### Extension: `citations` ####

Using an external filter, `pandoc-citeproc`, pandoc can automatically generate
citations and a bibliography in a number of styles.  Basic usage is

    pandoc --filter pandoc-citeproc myinput.txt

In order to use this feature, you will need to specify a bibliography file
using the `bibliography` metadata field in a YAML metadata section, or
`--bibliography` command line argument. You can supply multiple `--bibliography`
arguments or set `bibliography` metadata field to YAML array, if you want to
use multiple bibliography files.
The bibliography may have any of these formats:

  Format            File extension
  ------------      --------------
  BibLaTeX          .bib
  BibTeX            .bibtex
  Copac             .copac
  CSL JSON          .json
  CSL YAML          .yaml
  EndNote           .enl
  EndNote XML       .xml
  ISI               .wos
  MEDLINE           .medline
  MODS              .mods
  RIS               .ris

Note that `.bib` can be used with both BibTeX and BibLaTeX files;
use `.bibtex` to force BibTeX.

Note that `pandoc-citeproc --bib2json` and `pandoc-citeproc --bib2yaml`
can produce `.json` and `.yaml` files from any of the supported formats.

In-field markup: In BibTeX and BibLaTeX databases, pandoc-citeproc parses
a subset of LaTeX markup; in CSL YAML databases, pandoc markdown; and in CSL JSON databases, an [HTML-like markup][CSL markup specs]:

`<i>...</i>`
:   italics

`<b>...</b>`
:   bold

`<span style="font-variant:small-caps;">...</span>` or `<sc>...</sc>`
:   small capitals

`<sub>...</sub>`
:   subscript

`<sup>...</sup>`
:   superscript

`<span class="nocase">...</span>`
:   prevent a phrase from being capitalized as title case

`pandoc-citeproc -j` and `-y` interconvert the CSL JSON
and CSL YAML formats as far as possible.

As an alternative to specifying a bibliography file, you can include
the citation data directly in the `references` field of the
document's YAML metadata. The field should contain an array of
YAML-encoded references, for example:

    ---
    references:
    - type: article-journal
      id: WatsonCrick1953
      author:
      - family: Watson
        given: J. D.
      - family: Crick
        given: F. H. C.
      issued:
        date-parts:
        - - 1953
          - 4
          - 25
      title: 'Molecular structure of nucleic acids: a structure for deoxyribose
        nucleic acid'
      title-short: Molecular structure of nucleic acids
      container-title: Nature
      volume: 171
      issue: 4356
      page: 737-738
      DOI: 10.1038/171737a0
      URL: http://www.nature.com/nature/journal/v171/n4356/abs/171737a0.html
      language: en-GB
    ...

(`pandoc-citeproc --bib2yaml` can produce these from a bibliography file in one
of the supported formats.)

Citations and references can be formatted using any style supported by the
[Citation Style Language], listed in the [Zotero Style Repository].
These files are specified using the `--csl` option or the `csl` metadata field.
By default, `pandoc-citeproc` will use the [Chicago Manual of Style] author-date
format.  The CSL project provides further information on [finding and editing styles].

Citations go inside square brackets and are separated by semicolons.
Each citation must have a key, composed of '@' + the citation
identifier from the database, and may optionally have a prefix,
a locator, and a suffix.  The citation key must begin with a letter, digit,
or `_`, and may contain alphanumerics, `_`, and internal punctuation
characters (`:.#$%&-+?<>~/`).  Here are some examples:

    Blah blah [see @doe99, pp. 33-35; also @smith04, chap. 1].

    Blah blah [@doe99, pp. 33-35, 38-39 and *passim*].

    Blah blah [@smith04; @doe99].

`pandoc-citeproc` detects locator terms in the [CSL locale files].
Either abbreviated or unabbreviated forms are accepted. In the `en-US`
locale, locator terms can be written in either singular or plural forms,
as `book`, `bk.`/`bks.`; `chapter`, `chap.`/`chaps.`; `column`,
`col.`/`cols.`; `figure`, `fig.`/`figs.`; `folio`, `fol.`/`fols.`;
`number`, `no.`/`nos.`; `line`, `l.`/`ll.`; `note`, `n.`/`nn.`; `opus`,
`op.`/`opp.`; `page`, `p.`/`pp.`; `paragraph`, `para.`/`paras.`; `part`,
`pt.`/`pts.`; `section`, `sec.`/`secs.`; `sub verbo`, `s.v.`/`s.vv.`;
`verse`, `v.`/`vv.`; `volume`, `vol.`/`vols.`; `¶`/`¶¶`; `§`/`§§`. If no
locator term is used, "page" is assumed.

A minus sign (`-`) before the `@` will suppress mention of
the author in the citation.  This can be useful when the
author is already mentioned in the text:

    Smith says blah [-@smith04].

You can also write an in-text citation, as follows:

    @smith04 says blah.

    @smith04 [p. 33] says blah.

If the style calls for a list of works cited, it will be placed
at the end of the document.  Normally, you will want to end your
document with an appropriate header:

    last paragraph...

    # References

The bibliography will be inserted after this header.  Note that
the `unnumbered` class will be added to this header, so that the
section will not be numbered.

If you want to include items in the bibliography without actually
citing them in the body text, you can define a dummy `nocite` metadata
field and put the citations there:

    ---
    nocite: |
      @item1, @item2
    ...

    @item3

In this example, the document will contain a citation for `item3`
only, but the bibliography will contain entries for `item1`, `item2`, and
`item3`.

For LaTeX or PDF output, you can also use [`natbib`] or [`biblatex`]
to render bibliography. In order to do so, specify bibliography files as
outlined above, and add `--natbib` or `--biblatex` argument to `pandoc`
invocation. Bear in mind that bibliography files have to be in respective
format (either BibTeX or BibLaTeX).

[CSL markup specs]: http://docs.citationstyles.org/en/1.0/release-notes.html#rich-text-markup-within-fields
[Chicago Manual of Style]: http://chicagomanualofstyle.org
[Citation Style Language]: http://citationstyles.org
[Zotero Style Repository]: https://www.zotero.org/styles
[finding and editing styles]: http://citationstyles.org/styles/
[CSL locale files]: https://github.com/citation-style-language/locales

Non-pandoc extensions
---------------------

The following markdown syntax extensions are not enabled by default
in pandoc, but may be enabled by adding `+EXTENSION` to the format
name, where `EXTENSION` is the name of the extension.  Thus, for
example, `markdown+hard_line_breaks` is markdown with hard line breaks.

#### Extension: `lists_without_preceding_blankline` ####

Allow a list to occur right after a paragraph, with no intervening
blank space.

#### Extension: `hard_line_breaks` ####

Causes all newlines within a paragraph to be interpreted as hard line
breaks instead of spaces.

#### Extension: `ignore_line_breaks` ####

Causes newlines within a paragraph to be ignored, rather than being
treated as spaces or as hard line breaks.  This option is intended for
use with East Asian languages where spaces are not used between words,
but text is divided into lines for readability.

#### Extension: `tex_math_single_backslash` ####

Causes anything between `\(` and `\)` to be interpreted as inline
TeX math, and anything between `\[` and `\]` to be interpreted
as display TeX math.  Note: a drawback of this extension is that
it precludes escaping `(` and `[`.

#### Extension: `tex_math_double_backslash` ####

Causes anything between `\\(` and `\\)` to be interpreted as inline
TeX math, and anything between `\\[` and `\\]` to be interpreted
as display TeX math.

#### Extension: `markdown_attribute` ####

By default, pandoc interprets material inside block-level tags as markdown.
This extension changes the behavior so that markdown is only parsed
inside block-level tags if the tags have the attribute `markdown=1`.

#### Extension: `mmd_title_block` ####

Enables a [MultiMarkdown] style title block at the top of
the document, for example:

    Title:   My title
    Author:  John Doe
    Date:    September 1, 2008
    Comment: This is a sample mmd title block, with
             a field spanning multiple lines.

See the MultiMarkdown documentation for details.  If `pandoc_title_block` or
`yaml_metadata_block` is enabled, it will take precedence over
`mmd_title_block`.

[MultiMarkdown]: http://fletcherpenney.net/multimarkdown/

#### Extension: `abbreviations` ####

Parses PHP Markdown Extra abbreviation keys, like

    *[HTML]: Hypertext Markup Language

Note that the pandoc document model does not support
abbreviations, so if this extension is enabled, abbreviation keys are
simply skipped (as opposed to being parsed as paragraphs).

#### Extension: `autolink_bare_uris` ####

Makes all absolute URIs into links, even when not surrounded by
pointy braces `<...>`.

#### Extension: `ascii_identifiers` ####

Causes the identifiers produced by `auto_identifiers` to be pure ASCII.
Accents are stripped off of accented latin letters, and non-latin
letters are omitted.

#### Extension: `link_attributes` ####

Parses multimarkdown style key-value attributes on link and image references.
Note that pandoc's internal document model provides nowhere to put
these, so they are presently just ignored.

#### Extension: `mmd_header_identifiers` ####

Parses multimarkdown style header identifiers (in square brackets,
after the header but before any trailing `#`s in an ATX header).

#### Extension: `compact_definition_lists` ####

Activates the definition list syntax of pandoc 1.12.x and earlier.
This syntax differs from the one described above under [Definition lists]
in several respects:

  - No blank line is required between consecutive items of the
    definition list.
  - To get a "tight" or "compact" list, omit space between consecutive
    items; the space between a term and its definition does not affect
    anything.
  - Lazy wrapping of paragraphs is not allowed:  the entire definition must
    be indented four spaces.[^6]

[^6]:  To see why laziness is incompatible with relaxing the requirement
    of a blank line between items, consider the following example:

        bar
        :    definition
        foo
        :    definition

    Is this a single list item with two definitions of "bar," the first of
    which is lazily wrapped, or two list items?  To remove the ambiguity
    we must either disallow lazy wrapping or require a blank line between
    list items.

Markdown variants
-----------------

In addition to pandoc's extended markdown, the following markdown
variants are supported:

`markdown_phpextra` (PHP Markdown Extra)
:   `footnotes`, `pipe_tables`, `raw_html`, `markdown_attribute`,
    `fenced_code_blocks`, `definition_lists`, `intraword_underscores`,
    `header_attributes`, `abbreviations`, `shortcut_reference_links`.

`markdown_github` (GitHub-Flavored Markdown)
:   `pipe_tables`, `raw_html`, `tex_math_single_backslash`,
    `fenced_code_blocks`, `auto_identifiers`,
    `ascii_identifiers`, `backtick_code_blocks`, `autolink_bare_uris`,
    `intraword_underscores`, `strikeout`, `hard_line_breaks`,
    `shortcut_reference_links`.

`markdown_mmd` (MultiMarkdown)
:   `pipe_tables` `raw_html`, `markdown_attribute`, `link_attributes`,
    `raw_tex`, `tex_math_double_backslash`, `intraword_underscores`,
    `mmd_title_block`, `footnotes`, `definition_lists`,
    `all_symbols_escapable`, `implicit_header_references`,
    `auto_identifiers`, `mmd_header_identifiers`,
    `shortcut_reference_links`.

`markdown_strict` (Markdown.pl)
:   `raw_html`

Extensions with formats other than markdown
-------------------------------------------

Some of the extensions discussed above can be used with formats
other than markdown:

* `auto_identifiers` can be used with `latex`, `rst`, `mediawiki`,
  and `textile` input (and is used by default).

* `tex_math_dollars`, `tex_math_single_backslash`, and
  `tex_math_double_backslash` can be used with `html` input.
  (This is handy for reading web pages formatted using MathJax,
  for example.)

Producing slide shows with Pandoc
=================================

You can use Pandoc to produce an HTML + javascript slide presentation
that can be viewed via a web browser.  There are five ways to do this,
using [S5], [DZSlides], [Slidy], [Slideous], or [reveal.js].
You can also produce a PDF slide show using LaTeX [`beamer`].

Here's the markdown source for a simple slide show, `habits.txt`:

    % Habits
    % John Doe
    % March 22, 2005

    # In the morning

    ## Getting up

    - Turn off alarm
    - Get out of bed

    ## Breakfast

    - Eat eggs
    - Drink coffee

    # In the evening

    ## Dinner

    - Eat spaghetti
    - Drink wine

    ------------------

    ![picture of spaghetti](images/spaghetti.jpg)

    ## Going to sleep

    - Get in bed
    - Count sheep

To produce an HTML/javascript slide show, simply type

    pandoc -t FORMAT -s habits.txt -o habits.html

where `FORMAT` is either `s5`, `slidy`, `slideous`, `dzslides`, or `revealjs`.

For Slidy, Slideous, reveal.js, and S5, the file produced by pandoc with the
`-s/--standalone` option embeds a link to javascripts and CSS files, which are
assumed to be available at the relative path `s5/default` (for S5), `slideous`
(for Slideous), `reveal.js` (for reveal.js), or at the Slidy website at
`w3.org` (for Slidy).  (These paths can be changed by setting the `slidy-url`,
`slideous-url`, `revealjs-url`, or `s5-url` variables; see [Variables for slides],
above.) For DZSlides, the (relatively short) javascript and css are included in
the file by default.

With all HTML slide formats, the `--self-contained` option can be used to
produce a single file that contains all of the data necessary to display the
slide show, including linked scripts, stylesheets, images, and videos.

To produce a PDF slide show using beamer, type

    pandoc -t beamer habits.txt -o habits.pdf

Note that a reveal.js slide show can also be converted to a PDF
by printing it to a file from the browser.

Structuring the slide show
--------------------------

By default, the *slide level* is the highest header level in
the hierarchy that is followed immediately by content, and not another
header, somewhere in the document. In the example above, level 1 headers
are always followed by level 2 headers, which are followed by content,
so 2 is the slide level.  This default can be overridden using
the `--slide-level` option.

The document is carved up into slides according to the following
rules:

  * A horizontal rule always starts a new slide.

  * A header at the slide level always starts a new slide.

  * Headers *below* the slide level in the hierarchy create
    headers *within* a slide.

  * Headers *above* the slide level in the hierarchy create
    "title slides," which just contain the section title
    and help to break the slide show into sections.

  * A title page is constructed automatically from the document's title
    block, if present.  (In the case of beamer, this can be disabled
    by commenting out some lines in the default template.)

These rules are designed to support many different styles of slide show. If
you don't care about structuring your slides into sections and subsections,
you can just use level 1 headers for all each slide. (In that case, level 1
will be the slide level.) But you can also structure the slide show into
sections, as in the example above.

Note:  in reveal.js slide shows, if slide level is 2, a two-dimensional
layout will be produced, with level 1 headers building horizontally
and level 2 headers building vertically.  It is not recommended that
you use deeper nesting of section levels with reveal.js.

Incremental lists
-----------------

By default, these writers produce lists that display "all at once."
If you want your lists to display incrementally (one item at a time),
use the `-i` option. If you want a particular list to depart from the
default (that is, to display incrementally without the `-i` option and
all at once with the `-i` option), put it in a block quote:

    > - Eat spaghetti
    > - Drink wine

In this way incremental and nonincremental lists can be mixed in
a single document.

Inserting pauses
----------------

You can add "pauses" within a slide by including a paragraph containing
three dots, separated by spaces:

    # Slide with a pause

    content before the pause

    . . .

    content after the pause

Styling the slides
------------------

You can change the style of HTML slides by putting customized CSS files
in `$DATADIR/s5/default` (for S5), `$DATADIR/slidy` (for Slidy),
or `$DATADIR/slideous` (for Slideous),
where `$DATADIR` is the user data directory (see `--data-dir`, above).
The originals may be found in pandoc's system data directory (generally
`$CABALDIR/pandoc-VERSION/s5/default`). Pandoc will look there for any
files it does not find in the user data directory.

For dzslides, the CSS is included in the HTML file itself, and may
be modified there.

All [reveal.js configuration options] can be set through variables.
For example, themes can be used by setting the `theme` variable:

    -V theme=moon

Or you can specify a custom stylesheet using the `--css` option.

To style beamer slides, you can specify a `theme`, `colortheme`,
`fonttheme`, `innertheme`, and `outertheme`, using the `-V` option:

    pandoc -t beamer habits.txt -V theme:Warsaw -o habits.pdf

Note that header attributes will turn into slide attributes
(on a `<div>` or `<section>`) in HTML slide formats, allowing you
to style individual slides.  In beamer, the only header attribute
that affects slides is the `allowframebreaks` class, which sets the
`allowframebreaks` option, causing multiple slides to be created
if the content overfills the frame.  This is recommended especially for
bibliographies:

    # References {.allowframebreaks}

Speaker notes
-------------

reveal.js has good support for speaker notes.  You can add notes to your
markdown document thus:

    <div class="notes">
    This is my note.

    - It can contain markdown
    - like this list

    </div>

To show the notes window, press `s` while viewing the presentation.
Notes are not yet supported for other slide formats, but the notes
will not appear on the slides themselves.

Frame attributes in beamer
--------------------------

Sometimes it is necessary to add the LaTeX `[fragile]` option to
a frame in beamer (for example, when using the `minted` environment).
This can be forced by adding the `fragile` class to the header
introducing the slide:

    # Fragile slide {.fragile}

All of the other frame attributes described in Section 8.1 of
the [Beamer User's Guide] may also be used: `allowdisplaybreaks`,
`allowframebreaks`, `b`, `c`, `t`, `environment`, `label`, `plain`,
`shrink`.

EPUB Metadata
=============

EPUB metadata may be specified using the `--epub-metadata` option, but
if the source document is markdown, it is better to use a [YAML metadata
block][Extension: `yaml_metadata_block`].  Here is an example:

    ---
    title:
    - type: main
      text: My Book
    - type: subtitle
      text: An investigation of metadata
    creator:
    - role: author
      text: John Smith
    - role: editor
      text: Sarah Jones
    identifier:
    - scheme: DOI
      text: doi:10.234234.234/33
    publisher:  My Press
    rights: © 2007 John Smith, CC BY-NC
    ...

The following fields are recognized:

`identifier`
  ~ Either a string value or an object with fields `text` and
    `scheme`.  Valid values for `scheme` are `ISBN-10`,
    `GTIN-13`, `UPC`, `ISMN-10`, `DOI`, `LCCN`, `GTIN-14`,
    `ISBN-13`, `Legal deposit number`, `URN`, `OCLC`,
    `ISMN-13`, `ISBN-A`, `JP`, `OLCC`.

`title`
  ~ Either a string value, or an object with fields `file-as` and
    `type`, or a list of such objects.  Valid values for `type` are
    `main`, `subtitle`, `short`, `collection`, `edition`, `extended`.

`creator`
  ~ Either a string value, or an object with fields `role`, `file-as`,
    and `text`, or a list of such objects.  Valid values for `role` are
    [MARC relators], but
    pandoc will attempt to translate the human-readable versions
    (like "author" and "editor") to the appropriate marc relators.

`contributor`
  ~ Same format as `creator`.

`date`
  ~ A string value in `YYYY-MM-DD` format.  (Only the year is necessary.)
    Pandoc will attempt to convert other common date formats.

`lang` (or legacy: `language`)
  ~ A string value in [BCP 47] format.  Pandoc will default to the local
    language if nothing is specified.

`subject`
  ~ A string value or a list of such values.

`description`
  ~ A string value.

`type`
  ~ A string value.

`format`
  ~ A string value.

`relation`
  ~ A string value.

`coverage`
  ~ A string value.

`rights`
  ~ A string value.

`cover-image`
  ~ A string value (path to cover image).

`stylesheet`
  ~ A string value (path to CSS stylesheet).

`page-progression-direction`
  ~ Either `ltr` or `rtl`. Specifies the `page-progression-direction`
    attribute for the [`spine` element].

[MARC relators]: http://loc.gov/marc/relators/relaterm.html
[`spine` element]: http://idpf.org/epub/301/spec/epub-publications.html#sec-spine-elem

Literate Haskell support
========================

If you append `+lhs` (or `+literate_haskell`) to an appropriate input or output
format (`markdown`, `markdown_strict`, `rst`, or `latex` for input or output;
`beamer`, `html` or `html5` for output only), pandoc will treat the document as
literate Haskell source. This means that

  - In markdown input, "bird track" sections will be parsed as Haskell
    code rather than block quotations.  Text between `\begin{code}`
    and `\end{code}` will also be treated as Haskell code.  For
    ATX-style headers the character '=' will be used instead of '#'.

  - In markdown output, code blocks with classes `haskell` and `literate`
    will be rendered using bird tracks, and block quotations will be
    indented one space, so they will not be treated as Haskell code.
    In addition, headers will be rendered setext-style (with underlines)
    rather than ATX-style (with '#' characters). (This is because ghc
    treats '#' characters in column 1 as introducing line numbers.)

  - In restructured text input, "bird track" sections will be parsed
    as Haskell code.

  - In restructured text output, code blocks with class `haskell` will
    be rendered using bird tracks.

  - In LaTeX input, text in `code` environments will be parsed as
    Haskell code.

  - In LaTeX output, code blocks with class `haskell` will be rendered
    inside `code` environments.

  - In HTML output, code blocks with class `haskell` will be rendered
    with class `literatehaskell` and bird tracks.

Examples:

    pandoc -f markdown+lhs -t html

reads literate Haskell source formatted with markdown conventions and writes
ordinary HTML (without bird tracks).

    pandoc -f markdown+lhs -t html+lhs

writes HTML with the Haskell code in bird tracks, so it can be copied
and pasted as literate Haskell source.

Syntax highlighting
===================

Pandoc will automatically highlight syntax in [fenced code blocks] that
are marked with a language name.  The Haskell library [highlighting-kate] is used for
highlighting, which works in HTML, Docx, and LaTeX/PDF output.
The color scheme can be selected using the `--highlight-style` option.
The default color scheme is `pygments`, which imitates the default color
scheme used by the Python library pygments, but pygments is not actually
used to do the highlighting.

To see a list of language names that pandoc will recognize, type
`pandoc --version`.

To disable highlighting, use the `--no-highlight` option.

[highlighting-kate]: https://github.com/jgm/highlighting-kate

Custom writers
==============

Pandoc can be extended with custom writers written in [lua].  (Pandoc
includes a lua interpreter, so lua need not be installed separately.)

To use a custom writer, simply specify the path to the lua script
in place of the output format. For example:

    pandoc -t data/sample.lua

Creating a custom writer requires writing a lua function for each
possible element in a pandoc document.  To get a documented example
which you can modify according to your needs, do

    pandoc --print-default-data-file sample.lua

[lua]: http://www.lua.org

Authors
=======

© 2006-2015 John MacFarlane (jgm@berkeley.edu). Released under the
[GPL], version 2 or greater.  This software carries no warranty of
any kind.  (See COPYRIGHT for full copyright and warranty notices.)

Contributors include
Aaron Wolen,
Albert Krewinkel,
Alexander Kondratskiy,
Alexander Sulfrian,
Alexander V Vershilov,
Alfred Wechselberger,
Andreas Lööw,
Andrew Dunning,
Antoine Latter,
Arlo O'Keeffe,
Artyom Kazak,
Ben Gamari,
Beni Cherniavsky-Paskin,
Bjorn Buckwalter,
Bradley Kuhn,
Brent Yorgey,
Bryan O'Sullivan,
B. Scott Michel,
Caleb McDaniel,
Calvin Beck,
Christoffer Ackelman,
Christoffer Sawicki,
Clare Macrae,
Clint Adams,
Conal Elliott,
Craig S. Bosma,
Daniel Bergey,
Daniel T. Staal,
David Lazar,
David Röthlisberger,
Denis Laxalde,
Douglas Calvert,
Douglas F. Calvert,
Eric Kow,
Eric Seidel,
Florian Eitel,
François Gannaz,
Freiric Barral,
Fyodor Sheremetyev,
Gabor Pali,
Gavin Beatty,
Greg Maslov,
Grégory Bataille,
Greg Rundlett,
gwern,
Gwern Branwen,
Hans-Peter Deifel,
Henry de Valence,
Ilya V. Portnov,
infinity0x,
Jaime Marquínez Ferrándiz,
James Aspnes,
Jamie F. Olson,
Jan Larres,
Jason Ronallo,
Jeff Arnold,
Jeff Runningen,
Jens Petersen,
Jérémy Bobbio,
Jesse Rosenthal,
J. Lewis Muir,
Joe Hillenbrand,
John MacFarlane,
Jonas Smedegaard,
Jonathan Daugherty,
Josef Svenningsson,
Jose Luis Duran,
Julien Cretel,
Justin Bogner,
Kelsey Hightower,
Konstantin Zudov,
Lars-Dominik Braun,
Luke Plant,
Mark Szepieniec,
Mark Wright,
Masayoshi Takahashi,
Matej Kollar,
Mathias Schenner,
Matthew Pickering,
Matthias C. M. Troffaes,
Max Bolingbroke,
Max Rydahl Andersen,
mb21,
Merijn Verstraaten,
Michael Snoyman,
Michael Thompson,
MinRK,
Nathan Gass,
Neil Mayhew,
Nick Bart,
Nicolas Kaiser,
Nikolay Yakimov,
nkalvi,
Paulo Tanimoto,
Paul Rivier,
Peter Wang,
Philippe Ombredanne,
Phillip Alday,
Puneeth Chaganti,
qerub,
Ralf Stephan,
Recai Oktaş,
rodja.trappe,
RyanGlScott,
Scott Morrison,
Sergei Trofimovich,
Sergey Astanin,
Shahbaz Youssefi,
Shaun Attfield,
shreevatsa.public,
Simon Hengel,
Sumit Sahrawat,
takahashim,
thsutton,
Tim Lin,
Timothy Humphries,
Todd Sifleet,
Tom Leese,
Uli Köhler,
Václav Zeman,
Viktor Kronvall,
Vincent,
Wikiwide, and
Xavier Olive.

[GPL]: http://www.gnu.org/copyleft/gpl.html "GNU General Public License"