# Deprecated symbols Review symbols that are no longer in active development, and their recommended replacements. ## Overview Although these symbols are available for use, Apple is no longer actively developing them, and may remove them in a future release. Apple recommends moving away from these symbols and using their indicated replacements instead. Check the individual symbol pages for the recommended replacements. ## Topics ### Deprecated constants [`static const NSEventModifierFlags NSAlphaShiftKeyMask;`](/documentation/AppKit/NSAlphaShiftKeyMask) The Caps Lock key has been pressed. [`static const NSEventModifierFlags NSShiftKeyMask;`](/documentation/AppKit/NSShiftKeyMask) The Shift key has been pressed. [`static const NSEventModifierFlags NSControlKeyMask;`](/documentation/AppKit/NSControlKeyMask) The Control key has been pressed. [`static const NSEventModifierFlags NSAlternateKeyMask;`](/documentation/AppKit/NSAlternateKeyMask) The Option or Alt key has been pressed. [`static const NSEventModifierFlags NSCommandKeyMask;`](/documentation/AppKit/NSCommandKeyMask) The Command key has been pressed. [`static const NSEventModifierFlags NSNumericPadKeyMask;`](/documentation/AppKit/NSNumericPadKeyMask) A key in the numeric keypad or an arrow key has been pressed. [`static const NSEventModifierFlags NSHelpKeyMask;`](/documentation/AppKit/NSHelpKeyMask) The Help key has been pressed. [`static const NSEventModifierFlags NSFunctionKeyMask;`](/documentation/AppKit/NSFunctionKeyMask) A function key has been pressed. [`static const NSEventModifierFlags NSDeviceIndependentModifierFlagsMask;`](/documentation/AppKit/NSDeviceIndependentModifierFlagsMask) Device-independent modifier flags are masked. --- Copyright © 2026 Apple Inc. All rights reserved. | [Terms of Use](https://www.apple.com/legal/internet-services/terms/site.html) | [Privacy Policy](https://www.apple.com/privacy/privacy-policy)