Style Guide

There is a .editorconfig and a .clang-format file in the project root that defines some basic guidelines, mainly relating to indentation.

Code Formatting

We use clang-format for code formatting, the style rules are defined in .clang-format, before submitting a PR, make sure to run the following command on all the C++ files you changed:

clang-format -style=file -i <FILES>

Note: Depending on which file you change, this may produce a lot of changes because we have not run clang-format on all files in the project. This is fine.


Files use 2 spaces for indentation.

Line Width

Lines should not be longer than 120 characters, clang-format will enforce this when run. However, try to keep lines under 80 characters if it seems reasonable in the current situation.

In some cases it makes sense to have lines longer than 80 characters for readability. But long lines can just the same be unreadable, for example if you have long if-conditions or use complex expressions as function parameters. Make sure you only use longer lines if keeping it under 80 would be less readable.


Use Doxygen /** */ comments in front of functions, methods, types, members and classes:

 * @brief Generates a config object from a config file
 * For modularity the parsing and storing of the config is separated
class config_parser {
   * @brief Is used to resolve ${root...} references
  string m_barname;

For all other comments use // for single-line and /* */ for multi-line comments.

Your comments should describe the intent and purpose of your code, not necessarily what it does.

Header Files

Header files should end in .hpp.

We use pragmas instead of include guards to guarantee header files are included only once:

#pragma once