% Pandoc User's Guide % John MacFarlane % July 14, 2007 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] and (subsets of) [reStructuredText], [HTML], and [LaTeX], and it can write [markdown], [reStructuredText], [HTML], [LaTeX], [ConTeXt], [RTF], [DocBook XML], [groff man] pages, and [S5] HTML slide shows. Pandoc's version of markdown contains some enhancements, like footnotes and embedded LaTeX. In contrast to 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. [markdown]: http://daringfireball.net/projects/markdown/ [reStructuredText]: http://docutils.sourceforge.net/docs/ref/rst/introduction.html [S5]: http://meyerweb.com/eric/tools/s5/ [HTML]: http://www.w3.org/TR/html40/ [LaTeX]: http://www.latex-project.org/ [ConTeXt]: http://www.pragma-ade.nl/ [RTF]: http://en.wikipedia.org/wiki/Rich_Text_Format [DocBook XML]: http://www.docbook.org/ [groff man]: http://developer.apple.com/DOCUMENTATION/Darwin/Reference/ManPages/man7/groff_man.7.html [Haskell]: http://www.haskell.org/ © 2006-7 John MacFarlane (jgm at berkeley dot 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.) Recai Oktaş (roktas at debian dot org) deserves credit for the build system, the debian package, and the robust wrapper scripts. [GPL]: http://www.gnu.org/copyleft/gpl.html "GNU General Public License" Requirements ============ The `pandoc` program itself does not depend on any external libraries or programs. The wrapper script `html2markdown` requires - `pandoc` (which must be in the PATH) - a POSIX-compliant shell (installed by default on all linux and unix systems, including Mac OS X, and in [Cygwin] for Windows), - `HTML Tidy` - `iconv` (for character encoding conversion). (If `iconv` is absent, `html2markdown` will still work, but it will treat everything as UTF-8.) The wrapper script `markdown2pdf` requires - `pandoc` (which must be in the PATH) - a POSIX-compliant shell - `pdflatex`, which should be part of any [LaTeX] distribution - the following LaTeX packages (available from [CTAN], if they are not already included in your LaTeX distribution): + `unicode` + `fancyhdr` (if you have verbatim text in footnotes) + `graphicx` (if you use images) + `array` (if you use tables) + `ulem` (if you use strikeout text) The wrapper script `hsmarkdown` requires only a POSIX-compliant shell. [Cygwin]: http://www.cygwin.com/ [HTML Tidy]: http://tidy.sourceforge.net/ [`iconv`]: http://www.gnu.org/software/libiconv/ [CTAN]: http://www.ctan.org "Comprehensive TeX Archive Network" Using Pandoc ============ If you run `pandoc` without arguments, it will accept input from STDIN. If you run it with file names as arguments, it will take input from those files. By default, `pandoc` writes its output to STDOUT. If you want to write to a file, use the `-o` option: pandoc -o hello.html hello.txt Note that you can specify multiple input files on the command line. `pandoc` will concatenate them all (with blank lines between them) before parsing: pandoc -s ch1.txt ch2.txt refs.txt > book.html (The `-s` option here tells `pandoc` to produce a standalone HTML file, with a proper header, rather than a fragment. For more details on this and many other command-line options, see below.) 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 include `markdown`, `latex`, `context` (ConTeXt), `html`, `rtf` (rich text format), `rst` (reStructuredText), `docbook` (DocBook XML), `man` (groff man), and `s5` (which produces an HTML file that acts like powerpoint). Supported input formats include `markdown`, `html`, `latex`, and `rst`. Note that the `rst` reader only parses a subset of reStructuredText syntax. For example, it doesn't handle tables, option lists, or footnotes. But for simple documents it should be adequate. The `latex` and `html` readers are also limited in what they can do. Because the `html` reader is picky about the HTML it parses, it is recommended that you pipe HTML through [HTML Tidy] before sending it to `pandoc`, or use the `html2markdown` script described below. If you don't specify a reader or writer explicitly, `pandoc` will try to determine the input and output format 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. Character encodings ------------------- All input is assumed to be in the UTF-8 encoding, and all output is in UTF-8. If your local character encoding is not UTF-8 and you use accented or foreign characters, you should pipe the input and output through [`iconv`]. For example, iconv -t utf-8 source.txt | pandoc | iconv -f utf-8 > output.html will convert `source.txt` from the local encoding to UTF-8, then convert it to HTML, then convert back to the local encoding, putting the output in `output.html`. The shell scripts (described below) automatically convert the input from the local encoding to UTF-8 before running them through `pandoc`, then convert the output back to the local encoding. Shell scripts ============= Three shell scripts, `markdown2pdf`, `html2markdown`, and `hsmarkdown`, are included in the standard Pandoc installation. (They are not included in the Windows binary package, as they require a POSIX shell, but they may be used in Windows under Cygwin.) 1. `markdown2pdf` produces a PDF file from markdown-formatted text, using `pandoc` and `pdflatex`. The default behavior of `markdown2pdf` is to create a file with the same base name as the first argument and the extension `pdf`; thus, for example, markdown2pdf sample.txt endnotes.txt will produce `sample.pdf`. (If `sample.pdf` exists already, it will be backed up before being overwritten.) An output file name can be specified explicitly using the `-o` option: markdown2pdf -o book.pdf chap1 chap2 If no input file is specified, input will be taken from STDIN. All of `pandoc`'s options will work with `markdown2pdf` as well. 2. `html2markdown` grabs a web page from a file or URL and converts it to markdown-formatted text, using `tidy` and `pandoc`. All of `pandoc`'s options will work with `html2markdown` as well. In addition, the following special options may be used. The special options must be separated from the `html2markdown` command and any regular Pandoc options by the delimiter `--`: html2markdown -o out.txt -- -e latin1 -g curl google.com The `-e` or `--encoding` option specifies the character encoding of the HTML input. If this option is not specified, and input is not from STDIN, `html2markdown` will attempt to determine the page's character encoding from the "Content-type" meta tag. If this is not present, UTF-8 is assumed. The `-g` or `--grabber` option specifies the command to be used to fetch the contents of a URL: html2markdown -g 'curl --user foo:bar' www.mysite.com If this option is not specified, `html2markdown` searches for an available program (`wget`, `curl`, or a text-mode browser) to fetch the contents of a URL. 3. `hsmarkdown` is designed to be used as a drop-in replacement for `Markdown.pl`. It forces `pandoc` to convert from markdown to HTML, and to use the `--strict` flag for maximal compliance with official markdown syntax. (All of Pandoc's syntax extensions and variants, described below, are disabled.) No other command-line options are allowed. (In fact, options will be interpreted as filenames.) As an alternative to using the `hsmarkdown` shell script, the user may create a symbolic link to `pandoc` called `hsmarkdown`. When invoked under the name `hsmarkdown`, `pandoc` will behave as if the `--strict` flag had been selected, and no command-line options will be recognized. However, this approach does not work under Cygwin, due to problems with its simulation of symbolic links. Command-line options ==================== Various command-line options can be used to customize the output. For further documentation, see the `pandoc(1)` man page. `-f`, `--from`, `-r`, or `--read` *format* : specifies the input format (the format Pandoc will be converting *from*). *format* can be `native`, `markdown`, `rst`, `html`, or `latex`. `-t`, `--to`, `-w`, or `--write` *format* : specifies the output format -- the format Pandoc will be converting *to*. *format* can be `native`, `html`, `s5`, `docbook`, `latex`, `context`, `markdown`, `man`, `rst`, and `rtf`. `-s` or `--standalone` : indicates that a standalone document is to be produced (with appropriate headers and footers), rather than a fragment. `-o` or `--output` *filename* : sends output to *filename*. If this option is not specified, or if its argument is `-`, output will be sent to STDOUT. `-p` or `--preserve-tabs` : causes tabs in the source text to be preserved, rather than converted to spaces (the default). `--tabstop` *tabstop* : sets the number of spaces per tab to *tabstop* (defaults to 4). `--strict` : specifies that strict markdown syntax is to be used, without pandoc's usual extensions and variants (described below). When the input format is HTML, this means that constructs that have no equivalents in standard markdown (e.g. definition lists or strikeout text) will be parsed as raw HTML. `--reference-links` : causes reference-style links to be used in markdown and reStructuredText output. By default inline links are used. `-R` or `--parse-raw` : causes the HTML and LaTeX readers to parse HTML codes and LaTeX environments that it can't translate as raw HTML or LaTeX. Raw HTML can be printed in markdown, reStructuredText, HTML, 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.) `-C` or `--custom-header` *filename* : can be used to specify a custom document header. To see the headers used by default, use the `-D` option: for example, `pandoc -D html` prints the default HTML header. `--toc` or `--table-of-contents` : includes 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 with `man`, `docbook`, or `s5` output formats. `-c` or `--css` *filename* : allows the user to specify a custom stylesheet that will be linked to in HTML and S5 output. `-H` or `--include-in-header` *filename* : includes the contents of *filename* (verbatim) at the end of the document header. This can be used, for example, to include special CSS or javascript in HTML documents. `-B` or `--include-before-body` *filename* : includes the contents of *filename* (verbatim) at the beginning of the document body (e.g. after the `
` tag in HTML, or the `\begin{document}` command in LaTeX). This can be used to include navigation bars or banners in HTML documents. `-A` or `--include-after-body` *filename* : includes the contents of *filename* (verbatim) at the end of the document body (before the `` tag in HTML, or the `\end{document}` command in LaTeX). `-T` or `--title-prefix` *string* : includes *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). (See below on [Title Blocks](#title-blocks).) `-S` or `--smart` : causes `pandoc` to produce typographically correct output, along the lines of John Gruber's [Smartypants]. Straight quotes are converted to curly quotes, `---` to dashes, and `...` to ellipses. (Note: This option is only significant when the input format is `markdown`. It is selected automatically when the output format is `latex` or `context`.) `-m`*[url]* or `--asciimathml`*[=url]* : will cause LaTeX formulas (between $ signs) in HTML or S5 to display as formulas rather than as code. The trick will not work in all browsers, but it works in Firefox. Peter Jipsen's [ASCIIMathML] script is used to do the magic. If a local copy of `ASCIIMathML.js` is available on the webserver where the page will be viewed, provide a *url* and a link will be inserted in the generated HTML or S5. If no *url* is provided, the contents of the script will be inserted directly; this provides 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 `ASCIIMathML.js`, which can be cached. `-i` or `--incremental` : causes all lists in S5 output to be displayed incrementally by default (one item at a time). The normal default is for lists to be displayed all at once. `-N` or `--number-sections` : causes sections to be numbered in LaTeX or ConTeXt output. By default, sections are not numbered. `--dump-args` : is intended to make it easier to create wrapper scripts that use Pandoc. It causes Pandoc to dump information about the arguments with which it was called to STDOUT, then exit. The first line printed is the name of the output file specified using the `-o` or `--output` option, or `-` if output would go to STDOUT. The remaining lines, if any, list command-line arguments. These will include the names of input files and any special options passed after ` -- ` on the command line. So, for example, : pandoc --dump-args -o foo.html -s foo.txt \ appendix.txt -- -e latin1 : will cause the following to be printed to STDOUT: : foo.html foo.txt appendix.txt -e latin1 `--ignore-args` : causes Pandoc to ignore all command-line arguments. 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 `-v` or `--version` : prints the version number to STDERR. `-h` or `--help` : prints a usage message to STDERR. [Smartypants]: http://daringfireball.net/projects/smartypants/ [ASCIIMathML]: http://www1.chapman.edu/~jipsen/mathml/asciimath.html Pandoc's markdown vs. standard markdown ======================================= In parsing markdown, Pandoc departs from and extends [standard markdown] in a few respects. (To run Pandoc on the official markdown test suite, type `make test-markdown`.) Except where noted, these differences can be suppressed by specifying the `--strict` command-line option or by using the `hsmarkdown` wrapper. [standard markdown]: http://daringfireball.net/projects/markdown/syntax "Markdown syntax description" Backslash escapes ----------------- 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 *hello* instead of hello This rule is easier to remember than standard markdown's rule, which allows only the following characters to be backslash-escaped: \`*_{}[]()>#+-.! Subscripts and superscripts --------------------------- 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~`. Strikeout --------- To strikeout a section of text with a horizontal line, begin and end it with `~~`. Thus, for example, This ~~is deleted text.~~ Lists ----- Pandoc behaves differently from standard markdown on some "edge cases" involving lists. Consider this source: 1. First 2. Second: - Fee - Fie - Foe 3. Third Pandoc transforms this into a "compact list" (with no `` tags around "First", "Second", or "Third"), while markdown puts `
` 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 `--strict` option is specified. This
behavior is consistent with the official markdown syntax description,
even though it is different from that of `Markdown.pl`.)
Unlike standard markdown, Pandoc allows ordered list items to be marked
with uppercase and lowercase letters and roman numerals, in addition to
arabic numerals. (This behavior can be turned off using the `--strict`
option.) List markers may be enclosed in parentheses or followed by a
single right-parentheses or period. 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
Note that Pandoc pays attention only to the *starting* number in a list.
So, the following yields a list numbered sequentially starting from 2:
(2) Two
(5) Three
(2) Four
If default list markers are desired, use '`#.`':
#. one
#. two
#. three
If you change list style in mid-list, Pandoc will notice and assume you
are starting a sublist. So,
1. One
2. Two
A. Sub
B. Sub
3. Three
gets treated as if it were
1. One
2. Two
A. Sub
B. Sub
3. Three
Note that a list beginning with a single letter will be interpreted as
an alphabetic list. So you are out of luck if you want a roman-numbered
list starting with 100 (C).
Note also that a paragraph starting with a capital letter and a period
(for example, an initial) or a capital letter in parentheses
(for example, `(C)`) will be interpreted as a list:
B. Russell was an English philosopher.
(C) 2007 Joe Smith
To avoid this, use backslash escapes:
B\. Russell was an English philosopher.
\(C) 2007 Joe Smith
Definition lists
----------------
Pandoc supports definition lists, using a syntax inspired by
[PHP Markdown Extra] and [reStructuredText]:
[PHP Markdown Extra]: http://www.michelf.com/projects/php-markdown/extra/
Term 1
: Definition 1
Term 2
: Definition 2
: Second paragraph of definition 2.
Each term must fit on one line. The definition must begin on the line
after the term. The definition consists of one or more block elements
(paragraph, code block, list, etc.), each beginning with a colon and
(aside from the colon) indented one tab stop.
Term *with inline markup*
: Here is the definition. It may contain multiple blocks.
Here is some code:
: {* my code *}
: Here is the third paragraph of this definition.
If you leave space after the definition (as in the first example above),
the definitions will be considered paragraphs. In some output formats,
this will mean greater spacing between term/definition pairs. For a
compact definition list, do not leave space between the definition and
the next term:
Term 1
: Definition 1
Term 2
: Definition 2
Reference links
---------------
Pandoc allows implicit reference links with just a single set of
brackets. So, the following links are equivalent:
1. Here's my [link]
2. Here's my [link][]
[link]: linky.com
(Note: Pandoc works this way even if `--strict` is specified, because
`Markdown.pl` 1.0.2b7 allows single-bracket links.)
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.).
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.
Tables
------
Two kinds of tables may be used. Both kinds presuppose the use of
a fixed-width font, such as Courier.
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:[^1]
- 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).
[^1]: This scheme is due to Michel Fortin, who proposed it on the
Markdown discussion list:
into
*one*
[a link](http://google.com)
whereas `Markdown.pl` will preserve it as is.
There is one exception to this rule: text between `` 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 `
one
a link