GoLand 2021.1 Help

Extract constant

The Extract Constant refactoring makes your source code easier to read and maintain. It also helps you avoid using hardcoded constants without any explanations about their values or purpose.

Extract a constant

  1. In the editor, select an expression or declaration of a variable you want to replace with a constant.

  2. Press Ctrl+Alt+C to introduce a constant or select Refactor | Extract | Constant.

  3. Select an expression you want to extract as constant and press Enter. Select the number of occurrences you want to replace and a name you want to use.

Example of the extract a constant refactoring

Code snippet at GitHub

The Extract Constant refactoring helps you avoid using hardcoded constants without any explanations about their values or purpose.

Extract constant

Extract a constant

  1. In the editor, select an expression or declaration of a variable you want to replace with a constant.

  2. Press Ctrl+Alt+C to introduce a constant or select Refactor | Extract/Introduce | Constant from the main or context menu.

  3. If there are several expressions available for extracting, select the required one from the list that opens and press Enter.

  4. Select a name for the constant from the list of suggestions that opens or type a new one.

  5. Check the Put to header checkbox if you want the constant to be moved to the header file.

  6. Uncheck the Declare static checkbox if you don't want the constant to be declared as static.

  7. Press Enter.

Code example

BeforeAfter
@implementation PasswordValidator + (BOOL)isPasswordValid:(NSString *)password { // 4 will be extracted to a constant return password.length > 4; } @end
// Extracted constant static const int kMinPasswordLength = 4; @implementation PasswordValidator + (BOOL)isPasswordValid:(NSString *)password { return password.length > kMinPasswordLength; } @end
    Last modified: 08 March 2021