Documentation Standards

Sphinx

• The following characters are chosen for different heading levels: level 1 is = (equal sign), level 2 - (dash), level 3 ~ (tilde), level 4 . (dot) and level 5 " (double quote);
• Each line should break approximately after the first word that crosses the 72nd character (so most lines end up being 72-78 characters);
• The :: shorthand is preferred over .. code-block:: php to begin a PHP code block unless it results in the marker being on its own line (read the Sphinx documentation to see when you should use the shorthand);
• Inline hyperlinks are not used. Separate the link and their target definition, which you add on the bottom of the page;
• Inline markup should be closed on the same line as the open-string;

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Example
=======

When you are working on the docs, you should follow the
`Symfony Documentation`_ standards.

Level 2
-------

A PHP example would be::

    echo 'Hello World';

Level 3
~~~~~~~

.. code-block:: php

    echo 'You cannot use the :: shortcut here';

.. _`Symfony Documentation`: https://symfony.com/doc

Code Examples

• The code follows the Symfony Coding Standards as well as the Twig Coding Standards;
• The code examples should look real for a web application context. Avoid abstract or trivial examples (foo, bar, demo, etc.);
• The code should follow the Symfony Best Practices.
• Use Acme when the code requires a vendor name;
• Use example.com as the domain of sample URLs and example.org and example.net when additional domains are required. All of these domains are reserved by the IANA.
• To avoid horizontal scrolling on code blocks, we prefer to break a line correctly if it crosses the 85th character;
• When you fold one or more lines of code, place ... in a comment at the point of the fold. These comments are: // ... (PHP), # ... (Yaml/bash), {# ... #} (Twig), <!-- ... --> (XML/HTML), ; ... (INI), ... (text);
• When you fold a part of a line, e.g. a variable value, put ... (without comment) at the place of the fold;

• Description of the folded code: (optional)

  • If you fold several lines: the description of the fold can be placed after the ...;
  • If you fold only part of a line: the description can be placed before the line;
• If useful to the reader, a PHP code example should start with the namespace declaration;
• When referencing classes, be sure to show the use statements at the top of your code block. You don't need to show all use statements in every example, just show what is actually being used in the code block;
• If useful, a codeblock should begin with a comment containing the filename of the file in the code block. Don't place a blank line after this comment, unless the next line is also a comment;
• You should put a $ in front of every bash line.

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// src/Foo/Bar.php
namespace Foo;

use Acme\Demo\Cat;
// ...

class Bar
{
    // ...

    public function foo($bar): mixed
    {
        // set foo with a value of bar
        $foo = ...;

        $cat = new Cat($foo);

        // ... check if $bar has the correct value

        return $cat->baz($bar, ...);
    }
}

Files and Directories

• When referencing directories, always add a trailing slash to avoid confusions with regular files (e.g. "execute the console script located at the bin/ directory").
• When referencing file extensions explicitly, you should include a leading dot for every extension (e.g. "XML files use the .xml extension").

• When you list a Symfony file/directory hierarchy, use your-project/ as the top-level directory. E.g.

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  your-project/
  ├─ app/
  ├─ src/
  ├─ vendor/
  └─ ...

Images and Diagrams

• Diagrams must adhere to the Symfony docs style. These are created using the Dia application, to make sure everyone can edit them. See the README on GitHub for instructions on how to create them.

• All images and diagrams must contain alt descriptions:

  • Keep the descriptions concise, do not duplicate information surrounding the figure;
  • Describe complex diagrams in text surrounding the diagram instead of the alt description. In these cases, alt descriptions must describe where the longer description can be found (e.g. "These elements are described further in the next sections");
  • Start descriptions with a capital letter and end with a period;
  • Do not start with "A screenshot of", "Diagram of", etc. except when it's useful to know the exact type (e.g. a specific diagram type).

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.. image:: /_images/example-screenshot.png
    :alt: Some concise description of the screenshot.

.. raw:: html

    <object data="_images/example-diagram.svg" type="image/svg+xml"
        alt="Some concise description."
    ></object>

English Language Standards

Symfony documentation uses the United States English dialect, commonly called American English. The American English Oxford Dictionary is used as the vocabulary reference.

In addition, documentation follows these rules:

• Section titles: use a variant of the title case, where the first word is always capitalized and all other words are capitalized, except for the closed-class words (read Wikipedia article about headings and titles).

  E.g.: The Vitamins are in my Fresh California Raisins

• Punctuation: avoid the use of Serial (Oxford) Commas;
• Pronouns: avoid the use of nosism and always use you instead of we. (i.e. avoid the first person point of view: use the second instead);

• Gender-neutral language: when referencing a hypothetical person, such as "a user with a session cookie", use gender-neutral pronouns (they/their/them). For example, instead of:

  • he or she, use they
  • him or her, use them
  • his or her, use their
  • his or hers, use theirs
  • himself or herself, use themselves

• Avoid belittling words: Things that seem "obvious" or "simple" for the person documenting it, can be the exact opposite for the reader. To make sure everybody feels comfortable when reading the documentation, try to avoid words like:

  • basically
  • clearly
  • easy/easily
  • just
  • logically
  • merely
  • obviously
  • of course
  • quick/quickly
  • simply
  • trivial
• Contractions are allowed: e.g. you can write you would as well as you'd, it is as well as it's, etc.