Style Guidelines: Markdown

This document contains formatting standards for creating readable, consistent files using Markdown.

One problem I run into constantly when creating Markdown files is that I waste an ass-load of time fiddling with how the text looks before it gets parsed. Then, after I'm finished writing, I waste even more time adjusting what looks good in my text editor so that it looks good in a browser or Markdown viewer.

Being a masochist, I of course decided to create a guideline I could follow which would produce decent looking output without looking stupid in vim.

Basic conventions for Markdown files

Wrap all lines at 80 characters.
Denote bold text using the asterisk format: **bold text**.
Denote italic text using the underscore format: _emphasized text_.
Force a linebreak by ending a line with two spaces, no more.

Headings

Header text must use the atx-style with no closing # character.
Include a space between the # and the text of the Header^1.
```
# Header 1
## Header 2
### Header 3
```
Headers spanning more than 80 characters should be re-evaluated.
Headers must be preceded and followed by a newline except at the beginning of a file.

Lists

List items must be indented 2 spaces further than their parent.

Unordered list Items should use - instead of *.

This is arbitrary text, an unordered list begins on the next line.
  - list item 1
  - list item 2
    - sub-list item

The first level of list items must not be preceded by a newline.

All lists must be followed by newlines.

This text precedes a list of things.
  - list item 1
  - list item 2
    1. sub-list item 1
    2. sub-list item 2

  - list item 3
  - list item 4

This is text of any kind that follows a list.

List item lines exceeding 80 characters should, when wrapped, align vertically with the beginning of the preceding line's text.
```
  - Large, avian creatures, chocobos roughly act as the equivalent of
    horses, being domesticated for use as mounts...
```

Code

Inline code must use single backticks and must not have spaces between the backtick characters and the code.
```
# Bad
` .this-is-wrong `

# Good
`.this-is-good`
```
Fenced code blocks must be preceded and followed by a newline.

When used inside list items, fenced code blocks must be indented as if they were one level deeper that the list item that contains them.

  - This list item contains a fenced code block.
  - Let's show how it might interact with a list.

    ```
    .code-example {
      property: value;
    }
    ```

There is a newline above this paragraph because it is both the end of a
list and because it follows a fenced code block.

Tables

Like fenced code blocks, tables in Markdown are provided by Markdown Extra which seems to be pretty widely implemented.

Pipe characters must be preceded and followed by spaces for readability.
Table column width should be determined by the longest cell in the column.

Always format tables so they are readable in pre-processing.

# This is completely unreadable, although it is technically valid.
table header | other table header
--- | ---
table data | other table data

Never use preceding or trailing pipes when writing tables.

# This wastes our precious 80 character limit.
| table header | other table header |
| ------------ | ------------------ |
| table data   | table data         |

Tables must always be preceded and followed by newlines.

Table example:

This table meets all the criteria:

Group                     | Domain          | First Appearance
------------------------- | --------------- | ----------------
ShinRa                    | Mako Reactors   | FFVII
Moogles                   | MogNet          | FFIII
Vana'diel Chocobo Society | Chocobo Raising | FFXI:TOAU

A handsome table in pre-processed markdown is also handsome when rendered:

Group	Domain	First Appearance
ShinRa	Mako Reactors	FFVII
Moogles	MogNet	FFIII
Vana'diel Chocobo Society	Chocobo Raising	FFXI:TOAU

Footnotes

This is enforced locally through redcarpet2's configuration: :space_after_headers.

banj/markdown-styleguide