JetBrains Rider 2017.2 Help

Code Syntax Style: Optional Parentheses

In many cases, parentheses in expressions are optional. Sometimes they help you clarify precedence of operations - e.g. if ((a & b) | c), sometimes, however, they do not help at all and just add up to dead code - e.g. var d = a + (b + c);. JetBrains Rider will help you define where optional parentheses are helpful to you, and then either clean up the redundant parenthesis or automatically add missing ones where necessary.

JetBrains Rider helps you arrange optional parentheses in the existing code and takes your preferences into account when it produces new code with code completion and code generation features, applies code templates and performs refactorings.

Enforcing preferences for optional parentheses

By default, JetBrains Rider highlights parentheses that do not clarify operation precedence and helps remove them:

Removing redundant parentheses

Similarly, it notifies you about non-obvious operation precedences and suggests adding optional parentheses to make the code more readable:

Adding optional parentheses to clarify operation precedence

Another option to enforce your preferences for optional parentheses in a bulk mode is code cleanup. You can either run code cleanup with the default profile Default: Full Cleanup or run the cleanup with a custom profile solely targeted at your specific task as described below.

To apply preferences for optional parentheses with code cleanup

  1. Press Ctrl+Alt+S, or alternatively choose File | Settings on Windows and Linux or Rider | Preferences on macOS.
  2. Go to the Code Cleanup settings page: Editor | Code Cleanup.
  3. Create a new profile as described in the Code Cleanup section. In the Selected profile settings section for the new profile tick the Remove redundant parentheses and Add parentheses to explicitly specify operation precedence check boxes.
  4. Click Save to apply the modifications and let JetBrains Rider choose where to save them, or save the modifications to a specific settings layer using the Save To drop-down list. For more information, see layer-based settings.
  5. Select the scope where you want to enforce your preferences:
    • Set the caret anywhere in the file to enforce your preferences to the file.
    • Select one or more items in the Solution Explorer to enforce your preferences in the files under these nodes and their child items.
  6. Choose Code | Code Cleanup in the main menu.
  7. In the Code Cleanup dialog that opens, select the newly created profile.
  8. Click OK. JetBrains Rider will enforce your preferences in the selected scope.

Configuring preferences for optional parentheses

Your optional parentheses preferences are saved using the mechanism of layer-based settings. Among other things, this mechanism allows you to maintain different preferences for different solutions as well as to keep these preferences under a VCS and automatically share them with your team members.

To configure preferences for optional parentheses

  1. Go to the Editor | Code Style | C# page of JetBrains Rider settings (Ctrl+Alt+S), and then select the Code Style tab.
  2. In the Parentheses category, specify whether to remove redundant parentheses and which operations should be considered as not having obvious precedence.
  3. The selectors in the right column allow you to set severity levels of code inspections detecting code that differs from your preferences.
  4. Click Save to apply the modifications and let JetBrains Rider choose where to save them, or save the modifications to a specific settings layer using the Save To drop-down list. For more information, see layer-based settings.
Last modified: 21 November 2017

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