Browse Source
http://daringfireball.net/projects/markdown/syntax.text Last-Modified: Thu, 23 Oct 2008 17:06:38 GMTmaster
John Gruber
16 years ago
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Markdown: Syntax |
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================ |
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<ul id="ProjectSubmenu"> |
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<li><a href="/projects/markdown/" title="Markdown Project Page">Main</a></li> |
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<li><a href="/projects/markdown/basics" title="Markdown Basics">Basics</a></li> |
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<li><a class="selected" title="Markdown Syntax Documentation">Syntax</a></li> |
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<li><a href="/projects/markdown/license" title="Pricing and License Information">License</a></li> |
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<li><a href="/projects/markdown/dingus" title="Online Markdown Web Form">Dingus</a></li> |
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</ul> |
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|
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|
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* [Overview](#overview) |
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* [Philosophy](#philosophy) |
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* [Inline HTML](#html) |
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* [Automatic Escaping for Special Characters](#autoescape) |
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* [Block Elements](#block) |
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* [Paragraphs and Line Breaks](#p) |
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* [Headers](#header) |
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* [Blockquotes](#blockquote) |
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* [Lists](#list) |
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* [Code Blocks](#precode) |
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* [Horizontal Rules](#hr) |
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* [Span Elements](#span) |
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* [Links](#link) |
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* [Emphasis](#em) |
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* [Code](#code) |
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* [Images](#img) |
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* [Miscellaneous](#misc) |
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* [Backslash Escapes](#backslash) |
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* [Automatic Links](#autolink) |
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|
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**Note:** This document is itself written using Markdown; you |
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can [see the source for it by adding '.text' to the URL][src]. |
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[src]: /projects/markdown/syntax.text |
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* * * |
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<h2 id="overview">Overview</h2> |
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<h3 id="philosophy">Philosophy</h3> |
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Markdown is intended to be as easy-to-read and easy-to-write as is feasible. |
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Readability, however, is emphasized above all else. A Markdown-formatted |
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document should be publishable as-is, as plain text, without looking |
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like it's been marked up with tags or formatting instructions. While |
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Markdown's syntax has been influenced by several existing text-to-HTML |
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filters -- including [Setext] [1], [atx] [2], [Textile] [3], [reStructuredText] [4], |
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[Grutatext] [5], and [EtText] [6] -- the single biggest source of |
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inspiration for Markdown's syntax is the format of plain text email. |
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[1]: http://docutils.sourceforge.net/mirror/setext.html |
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[2]: http://www.aaronsw.com/2002/atx/ |
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[3]: http://textism.com/tools/textile/ |
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[4]: http://docutils.sourceforge.net/rst.html |
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[5]: http://www.triptico.com/software/grutatxt.html |
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[6]: http://ettext.taint.org/doc/ |
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|
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To this end, Markdown's syntax is comprised entirely of punctuation |
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characters, which punctuation characters have been carefully chosen so |
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as to look like what they mean. E.g., asterisks around a word actually |
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look like \*emphasis\*. Markdown lists look like, well, lists. Even |
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blockquotes look like quoted passages of text, assuming you've ever |
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used email. |
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<h3 id="html">Inline HTML</h3> |
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Markdown's syntax is intended for one purpose: to be used as a |
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format for *writing* for the web. |
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Markdown is not a replacement for HTML, or even close to it. Its |
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syntax is very small, corresponding only to a very small subset of |
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HTML tags. The idea is *not* to create a syntax that makes it easier |
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to insert HTML tags. In my opinion, HTML tags are already easy to |
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insert. The idea for Markdown is to make it easy to read, write, and |
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edit prose. HTML is a *publishing* format; Markdown is a *writing* |
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format. Thus, Markdown's formatting syntax only addresses issues that |
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can be conveyed in plain text. |
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For any markup that is not covered by Markdown's syntax, you simply |
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use HTML itself. There's no need to preface it or delimit it to |
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indicate that you're switching from Markdown to HTML; you just use |
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the tags. |
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The only restrictions are that block-level HTML elements -- e.g. `<div>`, |
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`<table>`, `<pre>`, `<p>`, etc. -- must be separated from surrounding |
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content by blank lines, and the start and end tags of the block should |
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not be indented with tabs or spaces. Markdown is smart enough not |
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to add extra (unwanted) `<p>` tags around HTML block-level tags. |
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For example, to add an HTML table to a Markdown article: |
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This is a regular paragraph. |
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<table> |
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<tr> |
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<td>Foo</td> |
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</tr> |
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</table> |
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This is another regular paragraph. |
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Note that Markdown formatting syntax is not processed within block-level |
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HTML tags. E.g., you can't use Markdown-style `*emphasis*` inside an |
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HTML block. |
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Span-level HTML tags -- e.g. `<span>`, `<cite>`, or `<del>` -- can be |
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used anywhere in a Markdown paragraph, list item, or header. If you |
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want, you can even use HTML tags instead of Markdown formatting; e.g. if |
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you'd prefer to use HTML `<a>` or `<img>` tags instead of Markdown's |
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link or image syntax, go right ahead. |
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Unlike block-level HTML tags, Markdown syntax *is* processed within |
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span-level tags. |
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<h3 id="autoescape">Automatic Escaping for Special Characters</h3> |
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In HTML, there are two characters that demand special treatment: `<` |
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and `&`. Left angle brackets are used to start tags; ampersands are |
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used to denote HTML entities. If you want to use them as literal |
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characters, you must escape them as entities, e.g. `<`, and |
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`&`. |
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Ampersands in particular are bedeviling for web writers. If you want to |
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write about 'AT&T', you need to write '`AT&T`'. You even need to |
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escape ampersands within URLs. Thus, if you want to link to: |
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http://images.google.com/images?num=30&q=larry+bird |
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you need to encode the URL as: |
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http://images.google.com/images?num=30&q=larry+bird |
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in your anchor tag `href` attribute. Needless to say, this is easy to |
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forget, and is probably the single most common source of HTML validation |
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errors in otherwise well-marked-up web sites. |
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Markdown allows you to use these characters naturally, taking care of |
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all the necessary escaping for you. If you use an ampersand as part of |
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an HTML entity, it remains unchanged; otherwise it will be translated |
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into `&`. |
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So, if you want to include a copyright symbol in your article, you can write: |
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© |
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and Markdown will leave it alone. But if you write: |
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AT&T |
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Markdown will translate it to: |
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AT&T |
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Similarly, because Markdown supports [inline HTML](#html), if you use |
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angle brackets as delimiters for HTML tags, Markdown will treat them as |
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such. But if you write: |
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4 < 5 |
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Markdown will translate it to: |
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4 < 5 |
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However, inside Markdown code spans and blocks, angle brackets and |
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ampersands are *always* encoded automatically. This makes it easy to use |
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Markdown to write about HTML code. (As opposed to raw HTML, which is a |
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terrible format for writing about HTML syntax, because every single `<` |
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and `&` in your example code needs to be escaped.) |
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* * * |
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<h2 id="block">Block Elements</h2> |
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<h3 id="p">Paragraphs and Line Breaks</h3> |
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A paragraph is simply one or more consecutive lines of text, separated |
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by one or more blank lines. (A blank line is any line that looks like a |
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blank line -- a line containing nothing but spaces or tabs is considered |
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blank.) Normal paragraphs should not be indented with spaces or tabs. |
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The implication of the "one or more consecutive lines of text" rule is |
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that Markdown supports "hard-wrapped" text paragraphs. This differs |
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significantly from most other text-to-HTML formatters (including Movable |
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Type's "Convert Line Breaks" option) which translate every line break |
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character in a paragraph into a `<br />` tag. |
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When you *do* want to insert a `<br />` break tag using Markdown, you |
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end a line with two or more spaces, then type return. |
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Yes, this takes a tad more effort to create a `<br />`, but a simplistic |
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"every line break is a `<br />`" rule wouldn't work for Markdown. |
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Markdown's email-style [blockquoting][bq] and multi-paragraph [list items][l] |
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work best -- and look better -- when you format them with hard breaks. |
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[bq]: #blockquote |
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[l]: #list |
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<h3 id="header">Headers</h3> |
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Markdown supports two styles of headers, [Setext] [1] and [atx] [2]. |
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Setext-style headers are "underlined" using equal signs (for first-level |
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headers) and dashes (for second-level headers). For example: |
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This is an H1 |
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============= |
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This is an H2 |
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------------- |
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Any number of underlining `=`'s or `-`'s will work. |
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Atx-style headers use 1-6 hash characters at the start of the line, |
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corresponding to header levels 1-6. For example: |
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# This is an H1 |
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## This is an H2 |
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###### This is an H6 |
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Optionally, you may "close" atx-style headers. This is purely |
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cosmetic -- you can use this if you think it looks better. The |
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closing hashes don't even need to match the number of hashes |
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used to open the header. (The number of opening hashes |
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determines the header level.) : |
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# This is an H1 # |
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## This is an H2 ## |
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### This is an H3 ###### |
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<h3 id="blockquote">Blockquotes</h3> |
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Markdown uses email-style `>` characters for blockquoting. If you're |
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familiar with quoting passages of text in an email message, then you |
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know how to create a blockquote in Markdown. It looks best if you hard |
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wrap the text and put a `>` before every line: |
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> This is a blockquote with two paragraphs. Lorem ipsum dolor sit amet, |
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> consectetuer adipiscing elit. Aliquam hendrerit mi posuere lectus. |
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> Vestibulum enim wisi, viverra nec, fringilla in, laoreet vitae, risus. |
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> |
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> Donec sit amet nisl. Aliquam semper ipsum sit amet velit. Suspendisse |
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> id sem consectetuer libero luctus adipiscing. |
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Markdown allows you to be lazy and only put the `>` before the first |
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line of a hard-wrapped paragraph: |
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> This is a blockquote with two paragraphs. Lorem ipsum dolor sit amet, |
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consectetuer adipiscing elit. Aliquam hendrerit mi posuere lectus. |
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Vestibulum enim wisi, viverra nec, fringilla in, laoreet vitae, risus. |
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> Donec sit amet nisl. Aliquam semper ipsum sit amet velit. Suspendisse |
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id sem consectetuer libero luctus adipiscing. |
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Blockquotes can be nested (i.e. a blockquote-in-a-blockquote) by |
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adding additional levels of `>`: |
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> This is the first level of quoting. |
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> |
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> > This is nested blockquote. |
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> |
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> Back to the first level. |
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Blockquotes can contain other Markdown elements, including headers, lists, |
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and code blocks: |
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> ## This is a header. |
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> |
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> 1. This is the first list item. |
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> 2. This is the second list item. |
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> |
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> Here's some example code: |
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> |
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> return shell_exec("echo $input | $markdown_script"); |
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Any decent text editor should make email-style quoting easy. For |
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example, with BBEdit, you can make a selection and choose Increase |
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Quote Level from the Text menu. |
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<h3 id="list">Lists</h3> |
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Markdown supports ordered (numbered) and unordered (bulleted) lists. |
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Unordered lists use asterisks, pluses, and hyphens -- interchangably |
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-- as list markers: |
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* Red |
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* Green |
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* Blue |
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is equivalent to: |
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+ Red |
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+ Green |
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+ Blue |
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and: |
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- Red |
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- Green |
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- Blue |
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Ordered lists use numbers followed by periods: |
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1. Bird |
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2. McHale |
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3. Parish |
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It's important to note that the actual numbers you use to mark the |
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list have no effect on the HTML output Markdown produces. The HTML |
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Markdown produces from the above list is: |
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<ol> |
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<li>Bird</li> |
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<li>McHale</li> |
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<li>Parish</li> |
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</ol> |
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If you instead wrote the list in Markdown like this: |
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1. Bird |
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1. McHale |
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1. Parish |
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or even: |
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3. Bird |
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1. McHale |
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8. Parish |
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you'd get the exact same HTML output. The point is, if you want to, |
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you can use ordinal numbers in your ordered Markdown lists, so that |
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the numbers in your source match the numbers in your published HTML. |
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But if you want to be lazy, you don't have to. |
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If you do use lazy list numbering, however, you should still start the |
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list with the number 1. At some point in the future, Markdown may support |
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starting ordered lists at an arbitrary number. |
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List markers typically start at the left margin, but may be indented by |
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up to three spaces. List markers must be followed by one or more spaces |
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or a tab. |
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To make lists look nice, you can wrap items with hanging indents: |
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* Lorem ipsum dolor sit amet, consectetuer adipiscing elit. |
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Aliquam hendrerit mi posuere lectus. Vestibulum enim wisi, |
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viverra nec, fringilla in, laoreet vitae, risus. |
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* Donec sit amet nisl. Aliquam semper ipsum sit amet velit. |
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Suspendisse id sem consectetuer libero luctus adipiscing. |
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But if you want to be lazy, you don't have to: |
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* Lorem ipsum dolor sit amet, consectetuer adipiscing elit. |
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Aliquam hendrerit mi posuere lectus. Vestibulum enim wisi, |
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viverra nec, fringilla in, laoreet vitae, risus. |
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* Donec sit amet nisl. Aliquam semper ipsum sit amet velit. |
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Suspendisse id sem consectetuer libero luctus adipiscing. |
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If list items are separated by blank lines, Markdown will wrap the |
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items in `<p>` tags in the HTML output. For example, this input: |
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* Bird |
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* Magic |
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will turn into: |
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<ul> |
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<li>Bird</li> |
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<li>Magic</li> |
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</ul> |
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But this: |
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* Bird |
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* Magic |
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will turn into: |
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<ul> |
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<li><p>Bird</p></li> |
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<li><p>Magic</p></li> |
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</ul> |
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List items may consist of multiple paragraphs. Each subsequent |
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paragraph in a list item must be indented by either 4 spaces |
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or one tab: |
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1. This is a list item with two paragraphs. Lorem ipsum dolor |
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sit amet, consectetuer adipiscing elit. Aliquam hendrerit |
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mi posuere lectus. |
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Vestibulum enim wisi, viverra nec, fringilla in, laoreet |
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vitae, risus. Donec sit amet nisl. Aliquam semper ipsum |
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sit amet velit. |
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2. Suspendisse id sem consectetuer libero luctus adipiscing. |
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It looks nice if you indent every line of the subsequent |
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paragraphs, but here again, Markdown will allow you to be |
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lazy: |
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* This is a list item with two paragraphs. |
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This is the second paragraph in the list item. You're |
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only required to indent the first line. Lorem ipsum dolor |
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sit amet, consectetuer adipiscing elit. |
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* Another item in the same list. |
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To put a blockquote within a list item, the blockquote's `>` |
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delimiters need to be indented: |
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* A list item with a blockquote: |
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> This is a blockquote |
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> inside a list item. |
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To put a code block within a list item, the code block needs |
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to be indented *twice* -- 8 spaces or two tabs: |
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* A list item with a code block: |
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<code goes here> |
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It's worth noting that it's possible to trigger an ordered list by |
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accident, by writing something like this: |
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1986. What a great season. |
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In other words, a *number-period-space* sequence at the beginning of a |
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line. To avoid this, you can backslash-escape the period: |
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1986\. What a great season. |
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<h3 id="precode">Code Blocks</h3> |
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Pre-formatted code blocks are used for writing about programming or |
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markup source code. Rather than forming normal paragraphs, the lines |
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of a code block are interpreted literally. Markdown wraps a code block |
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in both `<pre>` and `<code>` tags. |
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To produce a code block in Markdown, simply indent every line of the |
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block by at least 4 spaces or 1 tab. For example, given this input: |
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This is a normal paragraph: |
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This is a code block. |
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Markdown will generate: |
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<p>This is a normal paragraph:</p> |
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<pre><code>This is a code block. |
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</code></pre> |
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One level of indentation -- 4 spaces or 1 tab -- is removed from each |
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line of the code block. For example, this: |
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Here is an example of AppleScript: |
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|
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tell application "Foo" |
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beep |
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end tell |
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will turn into: |
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<p>Here is an example of AppleScript:</p> |
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<pre><code>tell application "Foo" |
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beep |
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end tell |
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</code></pre> |
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A code block continues until it reaches a line that is not indented |
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(or the end of the article). |
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Within a code block, ampersands (`&`) and angle brackets (`<` and `>`) |
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are automatically converted into HTML entities. This makes it very |
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easy to include example HTML source code using Markdown -- just paste |
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it and indent it, and Markdown will handle the hassle of encoding the |
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ampersands and angle brackets. For example, this: |
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<div class="footer"> |
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© 2004 Foo Corporation |
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</div> |
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will turn into: |
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<pre><code><div class="footer"> |
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&copy; 2004 Foo Corporation |
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</div> |
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</code></pre> |
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Regular Markdown syntax is not processed within code blocks. E.g., |
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asterisks are just literal asterisks within a code block. This means |
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it's also easy to use Markdown to write about Markdown's own syntax. |
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|
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|
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<h3 id="hr">Horizontal Rules</h3> |
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|
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You can produce a horizontal rule tag (`<hr />`) by placing three or |
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more hyphens, asterisks, or underscores on a line by themselves. If you |
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wish, you may use spaces between the hyphens or asterisks. Each of the |
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following lines will produce a horizontal rule: |
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* * * |
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*** |
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***** |
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- - - |
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--------------------------------------- |
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* * * |
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<h2 id="span">Span Elements</h2> |
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<h3 id="link">Links</h3> |
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|
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Markdown supports two style of links: *inline* and *reference*. |
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In both styles, the link text is delimited by [square brackets]. |
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|
|||
To create an inline link, use a set of regular parentheses immediately |
|||
after the link text's closing square bracket. Inside the parentheses, |
|||
put the URL where you want the link to point, along with an *optional* |
|||
title for the link, surrounded in quotes. For example: |
|||
|
|||
This is [an example](http://example.com/ "Title") inline link. |
|||
|
|||
[This link](http://example.net/) has no title attribute. |
|||
|
|||
Will produce: |
|||
|
|||
<p>This is <a href="http://example.com/" title="Title"> |
|||
an example</a> inline link.</p> |
|||
|
|||
<p><a href="http://example.net/">This link</a> has no |
|||
title attribute.</p> |
|||
|
|||
If you're referring to a local resource on the same server, you can |
|||
use relative paths: |
|||
|
|||
See my [About](/about/) page for details. |
|||
|
|||
Reference-style links use a second set of square brackets, inside |
|||
which you place a label of your choosing to identify the link: |
|||
|
|||
This is [an example][id] reference-style link. |
|||
|
|||
You can optionally use a space to separate the sets of brackets: |
|||
|
|||
This is [an example] [id] reference-style link. |
|||
|
|||
Then, anywhere in the document, you define your link label like this, |
|||
on a line by itself: |
|||
|
|||
[id]: http://example.com/ "Optional Title Here" |
|||
|
|||
That is: |
|||
|
|||
* Square brackets containing the link identifier (optionally |
|||
indented from the left margin using up to three spaces); |
|||
* followed by a colon; |
|||
* followed by one or more spaces (or tabs); |
|||
* followed by the URL for the link; |
|||
* optionally followed by a title attribute for the link, enclosed |
|||
in double or single quotes, or enclosed in parentheses. |
|||
|
|||
The following three link definitions are equivalent: |
|||
|
|||
[foo]: http://example.com/ "Optional Title Here" |
|||
[foo]: http://example.com/ 'Optional Title Here' |
|||
[foo]: http://example.com/ (Optional Title Here) |
|||
|
|||
**Note:** There is a known bug in Markdown.pl 1.0.1 which prevents |
|||
single quotes from being used to delimit link titles. |
|||
|
|||
The link URL may, optionally, be surrounded by angle brackets: |
|||
|
|||
[id]: <http://example.com/> "Optional Title Here" |
|||
|
|||
You can put the title attribute on the next line and use extra spaces |
|||
or tabs for padding, which tends to look better with longer URLs: |
|||
|
|||
[id]: http://example.com/longish/path/to/resource/here |
|||
"Optional Title Here" |
|||
|
|||
Link definitions are only used for creating links during Markdown |
|||
processing, and are stripped from your document in the HTML output. |
|||
|
|||
Link definition names may consist of letters, numbers, spaces, and |
|||
punctuation -- but they are *not* case sensitive. E.g. these two |
|||
links: |
|||
|
|||
[link text][a] |
|||
[link text][A] |
|||
|
|||
are equivalent. |
|||
|
|||
The *implicit link name* shortcut allows you to omit the name of the |
|||
link, in which case the link text itself is used as the name. |
|||
Just use an empty set of square brackets -- e.g., to link the word |
|||
"Google" to the google.com web site, you could simply write: |
|||
|
|||
[Google][] |
|||
|
|||
And then define the link: |
|||
|
|||
[Google]: http://google.com/ |
|||
|
|||
Because link names may contain spaces, this shortcut even works for |
|||
multiple words in the link text: |
|||
|
|||
Visit [Daring Fireball][] for more information. |
|||
|
|||
And then define the link: |
|||
|
|||
[Daring Fireball]: http://daringfireball.net/ |
|||
|
|||
Link definitions can be placed anywhere in your Markdown document. I |
|||
tend to put them immediately after each paragraph in which they're |
|||
used, but if you want, you can put them all at the end of your |
|||
document, sort of like footnotes. |
|||
|
|||
Here's an example of reference links in action: |
|||
|
|||
I get 10 times more traffic from [Google] [1] than from |
|||
[Yahoo] [2] or [MSN] [3]. |
|||
|
|||
[1]: http://google.com/ "Google" |
|||
[2]: http://search.yahoo.com/ "Yahoo Search" |
|||
[3]: http://search.msn.com/ "MSN Search" |
|||
|
|||
Using the implicit link name shortcut, you could instead write: |
|||
|
|||
I get 10 times more traffic from [Google][] than from |
|||
[Yahoo][] or [MSN][]. |
|||
|
|||
[google]: http://google.com/ "Google" |
|||
[yahoo]: http://search.yahoo.com/ "Yahoo Search" |
|||
[msn]: http://search.msn.com/ "MSN Search" |
|||
|
|||
Both of the above examples will produce the following HTML output: |
|||
|
|||
<p>I get 10 times more traffic from <a href="http://google.com/" |
|||
title="Google">Google</a> than from |
|||
<a href="http://search.yahoo.com/" title="Yahoo Search">Yahoo</a> |
|||
or <a href="http://search.msn.com/" title="MSN Search">MSN</a>.</p> |
|||
|
|||
For comparison, here is the same paragraph written using |
|||
Markdown's inline link style: |
|||
|
|||
I get 10 times more traffic from [Google](http://google.com/ "Google") |
|||
than from [Yahoo](http://search.yahoo.com/ "Yahoo Search") or |
|||
[MSN](http://search.msn.com/ "MSN Search"). |
|||
|
|||
The point of reference-style links is not that they're easier to |
|||
write. The point is that with reference-style links, your document |
|||
source is vastly more readable. Compare the above examples: using |
|||
reference-style links, the paragraph itself is only 81 characters |
|||
long; with inline-style links, it's 176 characters; and as raw HTML, |
|||
it's 234 characters. In the raw HTML, there's more markup than there |
|||
is text. |
|||
|
|||
With Markdown's reference-style links, a source document much more |
|||
closely resembles the final output, as rendered in a browser. By |
|||
allowing you to move the markup-related metadata out of the paragraph, |
|||
you can add links without interrupting the narrative flow of your |
|||
prose. |
|||
|
|||
|
|||
<h3 id="em">Emphasis</h3> |
|||
|
|||
Markdown treats asterisks (`*`) and underscores (`_`) as indicators of |
|||
emphasis. Text wrapped with one `*` or `_` will be wrapped with an |
|||
HTML `<em>` tag; double `*`'s or `_`'s will be wrapped with an HTML |
|||
`<strong>` tag. E.g., this input: |
|||
|
|||
*single asterisks* |
|||
|
|||
_single underscores_ |
|||
|
|||
**double asterisks** |
|||
|
|||
__double underscores__ |
|||
|
|||
will produce: |
|||
|
|||
<em>single asterisks</em> |
|||
|
|||
<em>single underscores</em> |
|||
|
|||
<strong>double asterisks</strong> |
|||
|
|||
<strong>double underscores</strong> |
|||
|
|||
You can use whichever style you prefer; the lone restriction is that |
|||
the same character must be used to open and close an emphasis span. |
|||
|
|||
Emphasis can be used in the middle of a word: |
|||
|
|||
un*frigging*believable |
|||
|
|||
But if you surround an `*` or `_` with spaces, it'll be treated as a |
|||
literal asterisk or underscore. |
|||
|
|||
To produce a literal asterisk or underscore at a position where it |
|||
would otherwise be used as an emphasis delimiter, you can backslash |
|||
escape it: |
|||
|
|||
\*this text is surrounded by literal asterisks\* |
|||
|
|||
|
|||
|
|||
<h3 id="code">Code</h3> |
|||
|
|||
To indicate a span of code, wrap it with backtick quotes (`` ` ``). |
|||
Unlike a pre-formatted code block, a code span indicates code within a |
|||
normal paragraph. For example: |
|||
|
|||
Use the `printf()` function. |
|||
|
|||
will produce: |
|||
|
|||
<p>Use the <code>printf()</code> function.</p> |
|||
|
|||
To include a literal backtick character within a code span, you can use |
|||
multiple backticks as the opening and closing delimiters: |
|||
|
|||
``There is a literal backtick (`) here.`` |
|||
|
|||
which will produce this: |
|||
|
|||
<p><code>There is a literal backtick (`) here.</code></p> |
|||
|
|||
The backtick delimiters surrounding a code span may include spaces -- |
|||
one after the opening, one before the closing. This allows you to place |
|||
literal backtick characters at the beginning or end of a code span: |
|||
|
|||
A single backtick in a code span: `` ` `` |
|||
|
|||
A backtick-delimited string in a code span: `` `foo` `` |
|||
|
|||
will produce: |
|||
|
|||
<p>A single backtick in a code span: <code>`</code></p> |
|||
|
|||
<p>A backtick-delimited string in a code span: <code>`foo`</code></p> |
|||
|
|||
With a code span, ampersands and angle brackets are encoded as HTML |
|||
entities automatically, which makes it easy to include example HTML |
|||
tags. Markdown will turn this: |
|||
|
|||
Please don't use any `<blink>` tags. |
|||
|
|||
into: |
|||
|
|||
<p>Please don't use any <code><blink></code> tags.</p> |
|||
|
|||
You can write this: |
|||
|
|||
`—` is the decimal-encoded equivalent of `—`. |
|||
|
|||
to produce: |
|||
|
|||
<p><code>&#8212;</code> is the decimal-encoded |
|||
equivalent of <code>&mdash;</code>.</p> |
|||
|
|||
|
|||
|
|||
<h3 id="img">Images</h3> |
|||
|
|||
Admittedly, it's fairly difficult to devise a "natural" syntax for |
|||
placing images into a plain text document format. |
|||
|
|||
Markdown uses an image syntax that is intended to resemble the syntax |
|||
for links, allowing for two styles: *inline* and *reference*. |
|||
|
|||
Inline image syntax looks like this: |
|||
|
|||
![Alt text](/path/to/img.jpg) |
|||
|
|||
![Alt text](/path/to/img.jpg "Optional title") |
|||
|
|||
That is: |
|||
|
|||
* An exclamation mark: `!`; |
|||
* followed by a set of square brackets, containing the `alt` |
|||
attribute text for the image; |
|||
* followed by a set of parentheses, containing the URL or path to |
|||
the image, and an optional `title` attribute enclosed in double |
|||
or single quotes. |
|||
|
|||
Reference-style image syntax looks like this: |
|||
|
|||
![Alt text][id] |
|||
|
|||
Where "id" is the name of a defined image reference. Image references |
|||
are defined using syntax identical to link references: |
|||
|
|||
[id]: url/to/image "Optional title attribute" |
|||
|
|||
As of this writing, Markdown has no syntax for specifying the |
|||
dimensions of an image; if this is important to you, you can simply |
|||
use regular HTML `<img>` tags. |
|||
|
|||
|
|||
* * * |
|||
|
|||
|
|||
<h2 id="misc">Miscellaneous</h2> |
|||
|
|||
<h3 id="autolink">Automatic Links</h3> |
|||
|
|||
Markdown supports a shortcut style for creating "automatic" links for URLs and email addresses: simply surround the URL or email address with angle brackets. What this means is that if you want to show the actual text of a URL or email address, and also have it be a clickable link, you can do this: |
|||
|
|||
<http://example.com/> |
|||
|
|||
Markdown will turn this into: |
|||
|
|||
<a href="http://example.com/">http://example.com/</a> |
|||
|
|||
Automatic links for email addresses work similarly, except that |
|||
Markdown will also perform a bit of randomized decimal and hex |
|||
entity-encoding to help obscure your address from address-harvesting |
|||
spambots. For example, Markdown will turn this: |
|||
|
|||
<address@example.com> |
|||
|
|||
into something like this: |
|||
|
|||
<a href="mailto:addre |
|||
ss@example.co |
|||
m">address@exa |
|||
mple.com</a> |
|||
|
|||
which will render in a browser as a clickable link to "address@example.com". |
|||
|
|||
(This sort of entity-encoding trick will indeed fool many, if not |
|||
most, address-harvesting bots, but it definitely won't fool all of |
|||
them. It's better than nothing, but an address published in this way |
|||
will probably eventually start receiving spam.) |
|||
|
|||
|
|||
|
|||
<h3 id="backslash">Backslash Escapes</h3> |
|||
|
|||
Markdown allows you to use backslash escapes to generate literal |
|||
characters which would otherwise have special meaning in Markdown's |
|||
formatting syntax. For example, if you wanted to surround a word |
|||
with literal asterisks (instead of an HTML `<em>` tag), you can use |
|||
backslashes before the asterisks, like this: |
|||
|
|||
\*literal asterisks\* |
|||
|
|||
Markdown provides backslash escapes for the following characters: |
|||
|
|||
\ backslash |
|||
` backtick |
|||
* asterisk |
|||
_ underscore |
|||
{} curly braces |
|||
[] square brackets |
|||
() parentheses |
|||
# hash mark |
|||
+ plus sign |
|||
- minus sign (hyphen) |
|||
. dot |
|||
! exclamation mark |
|||
|
Loading…
Reference in new issue