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Renaming Objective-C APIs for Swift

Use the NS_SWIFT_NAME macro to customize API names for Swift.

Overview

If you want to import an Objective-C API into Swift with a different name, use the NS_SWIFT_NAME macro. The macro preserves the Objective-C name for use with Objective-C code, so the API has appropriate names in each language.

You apply the NS_SWIFT_NAME macro to an individual type, method, or function declaration in Objective-C. After applying the macro, the name you use in your Swift code will be what you’ve chosen by using the macro.

Rename APIs

The example below renames a class and one of its properties:

NS_SWIFT_NAME(Sandwich.Preferences)
@interface SandwichPreferences : NSObject

@property BOOL includesCrust NS_SWIFT_NAME(isCrusty);

@end

@interface Sandwich : NSObject
@end

The SandwichPreferences class and its includesCrust property are renamed to Sandwich.Preferences and isCrusty for Swift:

var preferences = Sandwich.Preferences()
preferences.isCrusty = true

You use the NS_SWIFT_NAME macro as a prefix for classes and protocols. For all other kinds of declaration—such as properties, enumeration cases, and type aliases—you use the macro as a suffix. The following example uses the macro as a suffix to rename an enumeration:

typedef NS_ENUM(NSInteger, SandwichBreadType) {
    brioche, pumpernickel, pretzel, focaccia
} NS_SWIFT_NAME(SandwichPreferences.BreadType);

See Also

Customizing Objective-C APIs