Fuchsia.dev supports the markdown elements documented in this guide.

Blockquotes

Markdown uses the greater-than character (>) to render text as a blockquote (that is, quoted text).

This is a Markdown paragraph.

> This is a blockquote with two paragraphs. The first line of a blockquote
> paragraph has to have a greater-than character (`>`), but for readability
> in the source file, add a greater-than character to every subsequent line
> of the paragraph like this example. Though this isn't a requirement as
> shown in the second blockquote paragraph below.
>
> This is a second blockquote paragraph that only has a greater-than
character (`>`) for the first line. Donec sit amet nisl. Aliquam semper
ipsum sit amet velit. Suspendisse id sem consectetuer libero luctus
adipiscing. Lorem ipsum dolor sit amet, consectetuer adipiscing elit.
Aliquam hendrerit mi posuere lectus. Vestibulum enim wisi, viverra nec,
fringilla in, laoreet vitae, risus.

Code blocks

Code blocks are used to provide programmatic examples or markup source code. The content within a code block is not parsed like a normal Markdown paragraph but is instead rendered as it's written.

You can use code blocks to specify which programming language to render the code in for highlighting.

A blank line is required both before and after the three backticks (```). The backticks do not render in the final output. However, blank lines within a code block render in the final output.

Example 1: Uses Java syntax highlighting

```java
public class Hello {

  public static void main(String arg[]) {

    System.out.println("Hello.");
  }
}
```

Example 2: Prevents syntax highlighting

```none {:.devsite-disable-click-to-copy}
Some pseudo-code doesn't need syntax highlighting.
```

Example 3: Includes a replacement variable

```none {:.devsite-disable-click-to-copy}
Hello, my name is {{ '<var>' }}your-name{{ '</var>' }}.
```

<p>Example 1: Uses Java syntax highlighting</p>
<pre class="prettyprint lang-java"><code>public class Hello {<br/>public
static void main(String arg[]) {<br/>System.out.println("Hello.");<br/>}
<br/>}<br/></code></pre>
<p>Example 2: Prevents syntax highlighting</p>
<pre class="click-to-copy"><code><br/><p>Some pseudo-code doesn't need
syntax highlighting.</p><br/>
</code></pre>
<p>Example 3: Includes a replacement variable</p>
<pre class="no-prettyprint"><code><br/><p>Hello, my name is <var>your-name</var>.
</p><br/></code></pre>

public class Hello {

  public static void main(String arg[]) {

    System.out.println("Hello.");
  }
}

Some pseudo-code doesn't need syntax highlighting.

Hello, my name is your-name.

Using replaceable variables inside a code block

To use <var> tags in a code block, use Jinja expression brackets as follows:

{{ '<var>' }}PORT{{ '</var>' }}

The example above renders the following:

PORT

Comments

Fuchsia.dev supports single-line and multi-line comments in Markdown and HTML. The comments do not display on published pages. These comments are useful to alert contributors if your document contains includecode or MathJax.

Single-line comments

{# This is a single line comment #}

Multi-line comments

To use a multi-line comment on fuchsia.dev:

Wrap each line with {# ... #}. This works in both HTML and Markdown:

{# I wonder how drivers are doing? #}
{# I hear they are awesome! #}

Custom attributes

Fuchsia.dev allows you to set custom HTML attributes (such as class, id, or attribute='value') in Markdown files.

Supported Markdown elements

The following elements support custom attributes:

• Code spans
• Code blocks
• Headings
• Links
• Lists
• Paragraphs
• Tables and multi-line tables

Format

This is a Markdown paragraph.
{:.customClass #custom_id attribute='value'}

<p class="customClass" id="custom_id" attribute="value">This is a Markdown paragraph.</p>

Definition lists

To create a definition list in Markdown, list the term on a single line, then precede every definition with a colon (:) on a new line below the definition.

Apple
: A fruit
: A tech company

Orange
: A citrus fruit

    A definition can also contain other block or inline elements. This is a
    paragraph within the same definition as "A citrus fruit". Elements
    within must be indented four spaces to be recognized as part of the
    preceding definition.

: A color

<dl>
  <dt>Apple</dt>
  <dd>A fruit</dd>
  <dd>A tech company</dd>

  <dt>Orange</dt>
  <dd>
    <p>A citrus fruit</p>
    <p>
      A definition can also contain other block or inline elements. This is
      a paragraph within the same definition as "A citrus fruit". Elements
      within must be indented four spaces to be recognized as part of the
      preceding definition.
    </p>
  </dd>
  <dd>
    <p>A color</p>
  </dd>
</dl>

Emphasis and strong

Markdown uses asterisks (*) and underscores (_) for emphasis and strong formatting.

Emphasis

Text in one asterisk (*) or underscore (_) provides an italic style to specific text.

*single asterisks*

_single underscores_

supercali*fragilistic*expialidocious

supercali_fragilistic_expialidocious                 // won't format

<em>single asterisks</em>

<em>single underscores</em>

supercali<em>fragilistic</em>expialidocious

supercali_fragilistic_expialidocious

Strong

Text in double asterisks (**) or underscores (__) provides a bold style to specific text.

**double asterisks**

__double underscores__

supercali**fragilistic**expialidocious

supercali__fragilistic__expialidocious

<strong>double asterisks</strong>

<strong>double underscores</strong>

supercali<strong>fragilistic</strong>expialidocious

supercali<strong>fragilistic</strong>expialidocious

Escaping

Certain characters are reserved syntax in Markdown. To use a special character, use a backslash escape (\) to display the following literal characters:

\   backslash
`   backtick
*   asterisk
_   underscore
{}  curly braces
[]  square brackets
()  parentheses
#   hash mark
+   plus sign
-   minus sign (hyphen)
.   dot
!   exclamation mark

Footnotes

Footnotes are a useful tool for including additional or supplementary content without disrupting the flow of the page. The syntax is similar to reference links:

In the main text, include a label[^1] that starts with a caret.

[^1]: The footnote content goes here.

[^2]: Longer footnote content can be span multiple lines
    by indenting the continuation 4 spaces.

The footnote label can be any arbitrary string as long as it starts with a caret ^.

Headings

Markdown supports atx-style headers use between one and six hash characters (#) at the start of the line, which correspond to header levels one through six.

# This is an H1

## This is an H2

###### This is an H6

Header IDs

Fuchsia.dev supports custom HTML id attribute for every header. If you want to override the default id, add the custom attribute {#user_defined_name} at the end of the Markdown header.

# Working with contacts {#working-with-contacts}
## Contact Entry
### Contacts are working

<h1 id="working-with-contacts">Working with contacts</h1>
<h2 id="contact-entry">Contact Entry</h2>
<h3 id="contacts-are-working">Contacts are working</h3>

Table of contents

For every second- and third-level heading, fuchsia.dev automatically generates a table of contents (TOC) for the page. To hide headers from the TOC, add the custom attribute {:.hide-from-toc} at the end of the header.

## Hidden in TOC {:.hide-from-toc}             // try to find it!

Horizontal rules

Markdown supports a horizontal rule tag (<hr>) by placing three or more hyphens, asterisks, or underscores on a line.

Each of the following will produce a horizontal rule:

* * *

***

*****

- - -

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

Images

Markdown uses an image syntax that is intended to resemble the syntax for links, allowing for two styles: inline and reference.

Every image has the following properties:

• Starting exclamation mark: !.
• Set of square brackets, containing the alt attribute text.
• Set of parentheses, containing the URL or path to the image, and an optional title attribute enclosed in double or single quotes.
• Set of optional classes using custom attribute syntax {: .my-custom-css-class}

Inline syntax

The following are valid inline image syntax:

![Alt text](/docs/images/benchmarking/test_suite_example.png)

![Alt text](/docs/images/benchmarking/test_suite_example.png "Optional title")

![Alt text](/docs/images/benchmarking/test_suite_example.png "Optional title"){: .my-custom-css-class} 

Reference syntax

The following is reference-style image syntax:

![Alt text][ID]

Where ID is the name of a defined image reference. Image references are defined using syntax identical to link references:

[ID]: docs/images/benchmarking/test_suite_example.png  "Optional title attribute"

Custom syntax

You can specify the width of a Markdown image using the following syntax:

![Alt text](/docs/images/benchmarking/test_suite_example.png){: width="123"} 

Include code

The includecode tag includes a region of text from another file, especially a region of source code. The tag can also generate a downloadable file within the text, instead of including the text in the document.

You can use this tag to insert a portion of source code into a document, and maintain that source code as a runnable file.

The gerrit_repo+path parameter refers to a repository and path hosted on Gerrit or Git. The repo is in the format instance or repository and path is in the format of path/to/file.

{% includecode gerrit_repo="fuchsia/fuchsia" gerrit_path="examples/fidl/fuchsia.examples/types.test.fidl" %}

Including a portion of a file

There are three ways to specify a region of the file to include: region tags, regular expressions, and indented blocks.

{% includecode gerrit_repo="fuchsia/fuchsia" gerrit_path="examples/fidl/fuchsia.examples/types.test.fidl" region_tag="consts" %}

const BOARD_SIZE uint8 = 9;
const NAME string = "Tic-Tac-Toe";

{% includecode gerrit_repo="fuchsia/fuchsia" gerrit_path="examples/fidl/fuchsia.examples/types.test.fidl" regexp="WRITE = 0b010;" %}

WRITE = 0b010;

{% includecode gerrit_repo="fuchsia/fuchsia" gerrit_path="examples/fidl/fuchsia.examples/types.test.fidl" indented_block="type User" %}

type User = table {
    1: age uint8;
    2: name string:MAX_STRING_LENGTH;
};

Parameters

The following are optional parameters for includecode:

        bits FileMode : uint16 {
          READ = 0b001;
          WRITE = 0b010;
          EXECUTE = 0b100;
        };

        bits FileMode : uint16 {
          READ = 0b001;
          WRITE = 0b010;
          EXECUTE = 0b100;
        };

        bits FileMode : uint16 {
          READ = 0b001;
          WRITE = 0b010;
          EXECUTE = 0b100;
        };

            bits FileMode : uint16 {
              READ = 0b001;
              WRITE = 0b010;
              EXECUTE = 0b100;
            };

MAX_STRING_LENGTH echo_prefix, request<Echo> request);

MAX_STRING_LENGTH echo_prefix, request request);

      bits FileMode : uint16 {
        READ = 0b001;
        WRITE = 0b010;
        EXECUTE = 0b100;
      };

      bits FileMode : uint16 {
        WRITE = 0b010;
        EXECUTE = 0b100;
      };

Including markdown fragments

You can include Markdown files into your current Markdown file for normal processing using the << >> directive enclosing the required file path. The path must be relative to the current .md source file—absolute paths should not be used. The << >> directive is a block directive and so must appear on a line by itself.

For example, if the current file en/time-travel/example.md wants to include file en/time-travel/_samples/_sample.md, it would specify:

<<_samples/_sample.md>>

Inline code

You can indicate code within a Markdown paragraph by wrapping text with backtick quotes (`).

Use the `printf()` function. Code for the `printf()` function is located in the `system\ ` directory.

This sentence has inline `  {code}    ` with a lot of spaces but none are rendered.

<p>Use the <code>printf()</code> function. Code for the <code>printf()</code>
function is located in the <code>system\</code> directory.</p>
<p>This sentence has inline <code>{code}</code>with a lot of spaces but none
are rendered.</p>

Inline HTML

Markdown syntax does not offer the full versatility of HTML, however Markdown supports inline HTML. You can wrap your text in an HTML element tag such as:

This sentence is in Markdown with a <b>bold inline HTML tag</b>.

Links

Fuchsia.dev supports three style of links: inline, reference, and external. In all styles, the link text is delimited by [] (square brackets).

Inline links

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](https://fuchsia.dev/ "Title") inline link.

[This link](https://fuchsia.dev/) has no title attribute.

<p>This is <a href="https://fuchsia.dev/" title="Title">
an example</a> inline link.</p>

<p><a href="fuchsia.dev">This link</a> has no
title attribute.</p>

If you're referring to a local resource such as a file in the source tree, you can use relative paths. See the docs README for examples.

Reference links

Reference-style links use a second set of square brackets, inside which you provide a label 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, at the bottom of the document, you define your link at the bottom of the document, on a single line:

[id]: https://{{example_url}}/  "Optional Title Here"

External links

You can alert readers that a link will lead to an external site by adding {: .external} to the syntax. For example:

See the [official documentation](https://my_external_website){: .external} for details.

Links to Fuchsia source code or to Fuchsia changes are not external links.

Link syntax

Regardless of the way you create a markdown link in your content, you can link to various types of content from Fuchsia.dev:

• Content that is created by contributors that exists in the //docs directory of the Fuchsia source tree.

  Example: This is a link to //docs/get-started/learn-fuchsia.md:

  [Learn Fuchsia](/docs/get-started/learn-fuchsia.md)
  

• Content that is automatically generated such as fuchsia.dev/reference which does not exist in the Fuchsia source tree.

  Example: This is a link to the fuchsia.bluetooth generated API reference documentation:

  [`fuchsia.bluetooth`](https://fuchsia.dev/reference/fidl/fuchsia.bluetooth)
  

  Fuchsia also has non-generated reference content that exists in the //docs/reference/ directory. This type of content can be linked using the Fuchsia source tree content syntax.

• Links to a URL. These types of links must be marked as External.

  Example: This is a link to google.com:

  [`google.com`](https://google.com){: .external} 
  

Lists

Using Markdown syntax, you can easily create a bulleted or a numbered list. These are commonly known as unordered (that is bulleted) or ordered (that is numbered) lists since they refer to the generated (<ul>) and (<ol>) HTML tags.

Unordered lists

Unordered lists can use asterisks (*), pluses (+), or dashes (-) as list markers. The list renders the same, regardless of which marker you use.

This is a Markdown paragraph:
                                             // required blank line
* Red
* Green
* Blue

This is another Markdown paragraph:
                                            // required blank line
+ Red
+ Green
+ Blue

This is yet another Markdown paragraph:
                                            // required blank line
- Red
- Green
- Blue

<p>This is a Markdown paragraph:</p>
<ul>
  <li>Red</li>
  <li>Green</li>
  <li>Blue</li>
</ul>
<p>This is another Markdown paragraph:</p>
<ul>
  <li>Red</li>
  <li>Green</li>
  <li>Blue</li>
</ul>
<p>This is yet another Markdown paragraph:</p>
<ul>
  <li>Red</li>
  <li>Green</li>
  <li>Blue</li>
</ul>

Multi-level unordered lists

You can use asterisks (*), pluses (+), or dashes (-) for list markers in multi-level unordered lists. The second-level markers must precede by at least four spaces and remain consistent at every level. See the example below:

This is a Markdown paragraph:
                              // required blank line before parent list
 * Bird
     * Celtics
     * Retired
       * Larry                // extra space; not consistent w/ "Celtics"
 * Magic
     * Lakers

<p>This is a Markdown paragraph:</p>
<ul>
  <li>Bird
    <ul>
      <li>Celtics</li>
      <li>Retired</li>
      <ul>
        <li>Larry</li>
      </ul>
    </ul>
  </li>
  <li>Magic
    <ul>
      <li>Lakers</li>
    </ul>
  </li>
</ul>

Ordered lists

Ordered lists use a number and a period before the list item. You may define your own ordinal numbers in your ordered lists or use 1. for automatic numbering. See the example below:

This is a Markdown paragraph:
                                   // required blank line
1. Bird                            // recommended numbering
1. McHale
1. Parish

This is another Markdown paragraph:
                                   // required blank line
1. Bird                            // sequential numbering is allowed,
2. McHale                          // but not recommended
3. Parish

This is yet another Markdown paragraph:
                                   // required blank line
3. Bird                            // non-sequential numbering is allowed,
1. McHale                          // but not recommended
8. Parish

<p>This is a Markdown paragraph:</p>
<ol>
  <li>Bird</li>
  <li>McHale</li>
  <li>Parish</li>
</ol>
<p>This is another Markdown paragraph:</p>
<ol>
  <li>Bird</li>
  <li>McHale</li>
  <li>Parish</li>
</ol>
<p>This is yet another Markdown paragraph:</p>
<ol>
  <li>Bird</li>
  <li>McHale</li>
  <li>Parish</li>
</ol>

Multi-level ordered lists

You can create multi-level ordered lists; the second-level markers must precede by at least four spaces.

 1. Bird
     1. Lakers
 1. McHale
     1. Celtics

<ol>
  <li>Bird
    <ol>
      <li>Lakers</li>
    </ol>
  </li>
  <li>McHale
    <ol>
      <li>Celtics</li>
    </ol>
  </li>
</ol>

MathJax

The <devsite-mathjax> custom element allows you to display mathematical notation in fuchsia.dev content using MathJax 2.7. MathJax utilizes LaTeX syntax to create mathematical notion. See the LaTeX syntax guide to learn more.

Usage

To utilize MathJax in your document, you must include the custom element one time in your document:

  {# To see the fully rendered MathJax equations on this page,
  see the published page at https://fuchsia.dev/<PATH_TO_YOUR_DOCUMENT>#}
  <devsite-mathjax config="TeX-AMS-MML_SVG"></devsite-mathjax>

After including the custom element, you can write mathematical notion inside of a $$ block or $ inline.

Standalone block

<!-- <devsite-mathjax config="TeX-AMS-MML_SVG"></devsite-mathjax> -->

<div>
  $$
  R_{\mu\nu}-\frac{1}{2}Rg_{\mu\nu}+\Lambda{g_{\mu\nu}} = \frac{8\pi{G}}{c^4}{T_{\mu\nu}}
  $$
</div>

Inline

<!--Included only one time previously-->
<devsite-mathjax config="TeX-AMS-MML_SVG"></devsite-mathjax>

The area of a circle can be computed using the equation $ A = \pi{r^2} $,
where $ r $ is the radius of the circle, and $ \pi $ is the mathematical
constant that is approximately equal to 3.14159.

Paragraphs

A paragraph is simply one or more consecutive lines of text, separated by one or more blank lines. (A blank line is any line that looks like a blank line -- a line containing nothing but spaces or tabs is considered blank.) You do not need to indent normal paragraphs with spaces or tabs.

Tables

Markdown makes it easy to format tables with pipes (|) and hyphens (-). Deliminate text with pipes to create columns; a header row is defined when the following row has at least three hyphens for each column header.

Lesson                     | Description
------------------------   | ---------------------------------------
What is Fuchsia?           | An open source effort to create a production-grade operating system
What is FIDL?              | Fuchsia Interface Definition Language
Getting Started            | Download the Fuchsia source code

<table>
  <thead>
    <tr>
      <th>Lesson</th>
      <th>Description</th>
    </tr>
  </thead>
  <tbody>
    <tr>
      <td>What is Fuchsia?</td>
      <td>An open source effort to create a production-grade operating system</td>
    </tr>
    <tr>
      <td>What is FIDL?</td>
      <td>Fuchsia Interface Definition Language</td>
    </tr>
    <tr>
      <td>Getting Started</td>
      <td>Download the Fuchsia source code</td>
    </tr>
  </tbody>
</table>

Formatting text in a table

You can use Markdown syntax to format text within a table (that is, *emphasis*, **strong**, `code`). To align text within a column, add a colon : in the dash --- row to indicate direction (that is, left, center, right) as in the example below:

Left-aligned     | Center-aligned | Right-aligned
:---             |     :---:      |          ---:
info             | info           | info
more info        | more info      | more info
even *more* info | some `code`    | **not** code