The purpose of this description is to provide quick summary on documentation style used in `espressif/esp-idf`_ repository and how to add new documentation.
When documenting code for this repository, please follow `Doxygen style <http://doxygen.nl/manual/docblocks.html#specialblock>`_. You are doing it by inserting special commands, for instance ``@param``, into standard comments blocks, for example: ::
Doxygen supports couple of formatting styles. It also gives you great flexibility on level of details to include in documentation. To get familiar with available features, please check data rich and very well organized `Doxygen Manual <http://doxygen.nl/manual/index.html>`_.
The ultimate goal is to ensure that all the code is consistently documented, so we can use tools like `Sphinx`_ and `Breathe`_ to aid preparation and automatic updates of API documentation when the code changes.
1. Document all building blocks of code: functions, structs, typedefs, enums, macros, etc. Provide enough information about purpose, functionality and limitations of documented items, as you would like to see them documented when reading the code by others.
2. Documentation of function should describe what this function does. If it accepts input parameters and returns some value, all of them should be explained.
3. Do not add a data type before parameter or any other characters besides spaces. All spaces and line breaks are compressed into a single space. If you like to break a line, then break it twice.
7. Overview of functionality of documented header file, or group of files that make a library, should be placed in a separate ``README.rst`` file of the same directory. If this directory contains header files for different APIs, then the file name should be ``apiname-readme.rst``.
4. You may want to go even further and skip some code like repetitive defines or enumerations. In such case, enclose the code within ``/** @cond */`` and ``/** @endcond */`` commands. Example of such implementation is provided in :component_file:`driver/include/driver/gpio.h`.
6. Prepare one or more complete code examples together with description. Place description to a separate file ``README.md`` in specific folder of :idf:`examples` directory.
Standardize Document Format
-------------------------------
When it comes to text, please follow guidelines below to provide well formatted Markdown (.md) or reST (.rst) documents.
1. Please ensure that one paragraph is written in one line. Don't break lines like below. Breaking lines to enhance readability is only suitable for writing codes. To make the text easier to read, it is recommended to place an empty line to separate the paragraph.
:alt:One line for one paragraph - not recommend (click to enlarge)
No line breaks within the same paragraph (click to enlarge)
2. Please make the line number of CN and EN documents consistent like below. The benefit of this approach is that it can save time for both writers and translators. When non-bilingual writers need to update text, they only need to update the same line in the corresponding CN or EN document. For translators, if documents are updated in English, then translators can quickly locate where to update in the corresponding CN document later. Besides, by comparing the total number of lines in EN and CN documents, you can quickly find out whether the CN version lags behind the EN version.
