Work with source code
Code reference information
Doxygen documentation

Doxygen documentation

Last modified: 26 May 2024

Doxygen-style comments can be placed across the source code and used for generating fully-fledged documentation in various formats.

CLion includes the information from doxygen into the Quick Documentation popup Ctrl0Q:

Viewing doxygen documentation

Doxygen-styled information is included in Quick Documentation popup in addition to the type information. To invoke the documentation popup:

Place the caret at the desired symbol or at the @param command of the doxygen comment.
Press Ctrl0Q.

Alternatively, when the checkbox Show quick documentation on hover (Settings | Editor | General | Other) is selected, you can just move your mouse pointer over the desired symbol.

If function parameters are documented separately from the function description, CLion will merge all the comments and show you the full function’s signature documentation (the same way as doxygen does when generating the output) :

Creating doxygen comments

To create a doxygen comment from scratch:

Type one of the following symbols: ///, //!, /** or /*! and press Enter.
You will get a stub to fill with the documentation text:

To change the prefix type or to add the @brief tag:

In CLion Classic, go to Settings | Editor | Code Style | C/C++.
In CLion Nova, go to Languages & Frameworks | C/C++ | Code Generation.
CLion Classic
CLion Nova
Open the Code Generation tab and scroll down to the Documentation Comments section:
Scroll down to the Documentation Comment Template section:

Reliable rename

While renaming a function or its parameters, the doxygen comments need to be updated accordingly. In case of the Rename refactoring ShiftF6, CLion updates doxygen comments along with other references.

Before:

After:

Typing assistance

Basic typing assistance for doxygen commands is provisioned by CLion auto-complete feature:

Note that not all the commands are available in the completion. Here you can find the list of the commands that are currently unsupported.

Rendered view for doxygen comments

With CLion, doxygen comments can be shown in an easier-to-read format. In this Rendered View mode, items are shown grouped by their tags, while the tags themselves are skipped.

https://resources.jetbrains.com/help/img/idea/2024.1/cl_toggle_rendered_view.png

Note the rendered view limitations:

Opening the referenced web pages is not available.
EOL block comments are rendered only if they start the line.

Toggle and configure the rendered view

To enter the Rendered View mode, hover over a comment and click in the gutter or press CtrlAlt0Q. The icon turns into .
To quit the Rendered View mode, click in the gutter, or select Toggle Rendered View from the context menu of a doxygen comment, or press CtrlAlt0Q.
To turn on the Rendered View mode for all doxygen comments in the current file, select Render All Doc Comments from the context menu in the gutter.
If necessary, select Adjust Font Size from the context menu and change the font size using the slider.
To show all doxygen comments rendered by default, open the Settings dialog (CtrlAlt0S) , go to Editor | General | Appearance, and select the Render documentation comments checkbox.
To hide the Rendered View gutter icons, select Configure Gutter Icons from the context menu in the gutter and then clear the Documentation comments in-place rendering checkbox on the Settings | Editor | General | Gutter Icons page that opens.