This documentation is built using Sphinx, and an automatically generated API reference using Doxygen and Breathe.

We always welcome suggestions on how to improve our documentation, as well as pull requests with corrections and additions.

Building documentation

Please see the documentation prerequisites section for details on what you need in order to build the HPX documentation. Enable building of the documentation by setting HPX_WITH_DOCUMENTATION=ON during CMake configuration. To build the documentation, build the docs target using your build tool. The default output format is HTML documentation. You can choose alternative output formats (single-page HTML, PDF, and man) with the HPX_WITH_DOCUMENTATION_OUTPUT_FORMATS CMake option.


If you add new source files to the Sphinx documentation, you have to run CMake again to have the files included in the build.

Style guide

The documentation is written using reStructuredText. These are the conventions used for formatting the documentation:

  • Use, at most, 80 characters per line.

  • Top-level headings use over- and underlines with =.

  • Sub-headings use only underlines with characters in decreasing level of importance: =, - and ..

  • Use sentence case in headings.

  • Refer to common terminology using :term:`Component`.

  • Indent content of directives (.. directive::) by three spaces.

  • For C++ code samples at the end of paragraphs, use :: and indent the code sample by 4 spaces.

    • For other languages (or if you don’t want a colon at the end of the paragraph), use .. code-block:: language and indent by three spaces as with other directives.

  • Use .. list-table:: to wrap tables with a lot of text in cells.

API documentation

The source code is documented using Doxygen. If you add new API documentation either to existing or new source files, make sure that you add the documented source files to the doxygen_dependencies variable in docs/CMakeLists.txt.