CLion 2023.3 Help

Code Style. C/C++

Use this page to configure code style options for C/C++ files. When you change these settings, the Preview pane shows how this will affect your code.

Scheme

In this area, choose the code style scheme and change it as required. Code style scheme settings are automatically applied every time CLion generates, refactors, or reformats your code.

The IDE comes with two pre-defined schemes: the Project scheme and the Default scheme.

  • In the Project scheme, the settings that you configure apply only to your current project.

    These settings are stored in the codeStyles folder under .idea and are shared through VCS together with the project.

    The IDE creates the folder after you modify code style settings for your project.

  • In the Default scheme (IDE-level scheme), the settings that you configure apply to all existing projects that have the Default code style scheme selected.

    These settings are stored in the codestyles folder under the CLion configuration directory and are not shared through VCS.

If you want to use the project code style scheme as your default scheme, you can copy it to the IDE level. The other way around is also possible: you can overwrite your current project settings with the settings from an IDE-level scheme and share them with other members of your team.

Item

Description

Scheme

From this list, select the scheme to be used. The predefined schemes are shown bold. The custom schemes, ones created as copies of the predefined schemes, are in plain text. The location where the scheme is stored is written next to each scheme, for example, the Default scheme is stored in the IDE, the Project scheme is stored in the project.

Show Scheme Actions

Click this button to invoke the list of commands to manage the schemes:

  • Copy to IDE: select this option to copy the scheme settings to CLion.

  • Export: select this option to export the selected scheme in the IntelliJ IDEA code style XML or .clang-format File format (if the CLang Format plugin is enabled) .

  • Import Scheme: select this option to import the scheme of the selected type from the specified location.

  • Copy to Project: select this option to overwrite your current project code style settings with the settings from the selected IDE code style scheme.

  • Duplicate: select this option to create a copy of the selected scheme.

  • Reset: select this option to reset the default or bundled color scheme to the initial defaults shipped with CLion. This command becomes available only if some changes have been done.

  • Rename: select this option to change the name of the selected custom scheme. Press Enter to save changes, or Escape to cancel.

Set from

Click this link and choose the language to be used as the base for the current language code style. The list contains the following options:

Item

Description

Language

Choose this option to inherit the code style settings from another language. Select the source language from the list, that opens. So doing, only the settings that are applicable to the current language are taken. All the other settings are not affected.

Predefined Style

Choose this option to use one of the well-known code style guidelines. Select one of the following standards from the list.

Note: each code style affects only the certain items of base settings and leaves the rest unchanged.

The following styles are applicable for braces placement only:

Tabs and Indents

Item

Description

Use tab character

  • If this checkbox is selected, tab characters are used:

    • On pressing the Tab key

    • For indentation

    • For code reformatting

  • When the checkbox is cleared, CLion uses spaces instead of tabs.

Smart tabs

  • If this checkbox is selected, the part of indentation defined by the nesting of code blocks, is made of the tabs and (if necessary) spaces, while the part of indentation defined by the alignment is made only of spaces.

  • If this checkbox is cleared, only tabs are used. This means that a group of spaces that fits the specified tab size is automatically replaced with a tab, which may result in breaking fine alignment.

The Smart tabs checkbox is available if the Use tab character checkbox is selected.

Tab size

In this field, specify the number of spaces included in a tab.

Continuation indent

In this field, specify the number of spaces to be inserted between the elements of an array, in expressions, method declarations and method calls.

Keep indents on empty lines

If this checkbox is selected, CLion will keep indents on the empty lines as if they contained some code.

If this checkbox is cleared, CLion will delete the tab characters and spaces.

Label indent

In this field, specify the number of spaces to be inserted at the next line before a label statement.

Absolute label indent

If this checkbox is selected, label indentation is counted as an absolute number of spaces. Otherwise, label indentation is counted relative to previous indent levels.

Indent in lambdas

In this field, type the indent of lambda expressions.

Indent members of plain structures

In this field, type the indent of the plain structure members.

Indent members of classes

In this field, type the indent of the class members.

Indent visibility keywords in class/structure

In this field, type the indent of the visibility keywords (public, protected, etc).

Indent members of namespace

In this field, type the indent of members of namespaces.

Preprocessor directive indent

In this field type the indent of preprocessor directives.

Follow code indent

Select this checkbox to keep the indent of preprocessor directives equal to that of surrounding code lines.

Spaces

Use this tab to specify where you want spaces in your code. To have CLion automatically insert a space at a location, select the checkbox next to this location in the list. The results are displayed in the preview pane.

Wrapping and Braces

In this tab, customize the code style options, which CLion will apply on reformatting the source code. The left-hand pane contains the list of exceptions (Keep when reformatting), and placement and alignment options for the various code constructs (lists, statements, operations, annotations, and so on) The right-hand pane shows the preview.

Alignment takes precedence over indentation options.

Hard wrap at

Use the Hard wrap at field to specify a margin space required on the right side of an element. If you select the Default option, then a value of the right margin from the global settings is used.

Wrap on typing

Use the Wrap on typing settings to specify how the edited text is fitted in the specified Hard wrap at:

  • Default: in this case CLion uses the Wrap on typing option that is specified in the global settings.

  • Yes: in this case CLion uses the value specified in the Right Margin field.

  • No: in this case this option is switched off and a line can exceed the value specified in the right margin.

Visual guides

Use the Visual guides field to specify multiple right margins. You can leave a default value or enter the number of spaces for your margin. If you want to specify several margins, enter numbers separated by comma.

Keep when reformatting

Use the checkboxes to configure exceptions that CLion will make when reformatting the source code. For example, by default, the Line breaks checkbox is selected. If your code contains lines that are shorter than a standard convention, you can convert them by disabling the Line breaks checkbox before you reformat the source code.

Braces placement options

Item

Description

Braces placement style

Use this list to specify the position of the opening brace in class declarations, function declarations and other types of declarations. The available options are:

  • End of line: select this option to have the opening brace placed at the declaration line end.

  • Next line if wrapped: select this option to have the opening brace placed at the beginning of the line after the multiline declaration line.

  • Next line: select this option to have the opening brace placed at the beginning of the line after the declaration line.

  • Next line shifted: select this option to have the opening brace placed at the line after the declaration line being shifted to the corresponding indent level.

  • Next line, each shifted: select this option to have the opening brace placed at the line after the declaration line being shifted to the corresponding indent level, and have the next line shifted to the next indent level as well.

Force braces

From this list, choose the braces introduction method for if, for, while, and do () while statements. The available options are:

  • Do not force: select this option to suppress introducing braces automatically.

  • When multiline: select this option to have braces introduced automatically if a statement occupies more than one line. Note that CLion analyzes the number of lines in the entire statement but not only its condition.

    For example, if the code is

    int foo (int Days) { if ((Days % 10) == 3) return 1; else return 0; }

    CLion will insert braces automatically:

    int foo (int Days) { if ((Days % 10) == 3) { return 1; } else { return 0; } }
  • Always: select this checkbox to have braces always introduced automatically.

Blank lines

Use this tab to define where and how many blank lines you want CLion to retain and insert in your code after reformatting. For each type of location, specify the number of blank lines to be inserted. The results are displayed in the preview pane.

Item

Description

Keep maximum blank lines

In this area, specify the number of blank lines to be kept after reformatting in the specified locations.

Minimum blank lines

In this area, specify the number of blank lines to be present in the specified locations.

New File Extensions

In this tab you can define the source/header file types used in the Create New C/C++ Source File dialog. This tab also determines the order of their appearance in the Type field of that dialog: the first pair in the tab is the first extension in the type list in dialog.

Item

Description

Source/header file types pane.

The list of source and header file types. All the code style rules specified under this node of Settings, are applicable to the listed file types.

Source Extension

From the drop-down list, choose the extension to be associated with the source files.

Header Extension

From the drop-down list, choose the extension to be associated with the header files.

File Naming Convention

Choose the preferred naming convention from the drop down list. This setting defines a case of the file name generated in the New C++ Class dialog when a new class is being created.

Item

Shortcut

Description

Alt+Insert

Click this button to add a new source/header file types pair to the list. The new pair is always of .cpp/.h type. When added to the list, assign the desired extensions from the Source Extension/Header Extension dropdown lists to them.

Alt+Delete

Click this button to remove the selected source/header file types pair from the list.

Alt+Up or Alt+Down

Use these buttons to move the selected source/header file types pair up and down in the list.

Code Generation

Item

Description

General

  • Line comment at first column: If this checkbox is selected, line comments will be aligned at the first column; otherwise, they will be aligned at the code.

  • Block comment at first column: If this checkbox is selected, block comments will be aligned at the first column; otherwise, they will be aligned at the code.

  • Indent new lines in block comments: If this checkbox is selected, each next line of the block code will be indented; otherwise, it will be aligned with the first line of the block.

  • Const/volatile qualifier placement. The setting defines the keywords order during the code generation.

    Select the const int x = 0 radio button to place the const/volatile qualifier before a type specifier. Select the int const x = 0 radio button to place the const/volatile qualifier between the type specifier and the symbol name.

C++

  • Prefix for fields: type a prefix that will prepend a name of an automatically generated field.

  • Suffix for fields: type a suffix that will be appended to a name of an automatically generated field.

  • Prefix for getters: type a prefix that will prepend a name of an automatically generated getter. The default name is get.

  • Prefix for setters: type a prefix that will prepend a name of an automatically generated setter. The default name is set.

  • Generate != together with ==: select this checkbox to enable this setting as default for Select Fields dialog when generating an equality operator.

  • Generate >,<=,>= together with <: select this checkbox to enable this setting as default for Select Fields dialog when generation a relational operator.

  • Insert "virtual" attribute together with "override": select this checkbox to allow inserting the "virtual" attribute together with "override" specifier for inherited functions being generated. This option is available since C++11 standard or later.

  • Use C++ cast operators: when selected, quick fixes will insert C++ cast operators instead of C-style casts when appropriate.

Documentation comments

  • Add @brief tag: select this checkbox to enable the @brief tag in Doxygen-style comments.

  • Tag prefix in line comments: click @param or \param radio button to select the preferred prefix type.

  • Tag prefix in block comments: click @param or \param radio button to select the preferred prefix type.

Naming Convention

See Naming conventions.

Last modified: 15 March 2024