For the record, I needed to use Alfred spell command to be able to spell interoperability correctly …

Anyways, some time ago, Apple introduced NS_ENUM and NS_OPTIONS to Objective-C. Back then, it wasn’t a huge improvement to warrant rolling out these macros that were pretty much handled properly by their C counterparts. However…

If one had a mind as sharp as Kenpachi’s sword, then maybe they’d smelled the scent of what about to come

image

First, there was the introduction of the 64-bit devices. Sure, it’s ambiguous to know the size backing those enums, but I mean, if you’re that much of an enum fan, I doubt anyone would want to touch your code.

The big cheese introduced this year, namely Swift, actually benefits greatly from those macros (I think they later turned into actual identifiers). When your Objective-C enums are defined using NS_ENUM and NS_OPTIONS, they are properly ported to swift enums when accessed from swift. Here is an example taken directly from my app:

typedef NS_ENUM(NSInteger, ESettingsCellType) {
    ESettingsCellPlain,
    ESettingsCellOptions,
    ESettingsCellSegmented,
    ESettingsCellSwitch,
    ESettingsCellSlider,
    ESettingsCellButton,
    ESettingsCellCheckmark,
    ESettingsCellDownload
};
private let reuseMap: [ESettingsCellType:String] = [
    .Plain     : "disclosure",
    .Options   : "options",
    .Segmented : "picker",
    .Switch    : "picker",
    .Slider    : "picker",
    .Button    : "disclosure",
    .Checkmark : "checkmark",
    .Download  : "download",
]

I am guilty of not using NS_ENUM at first, since this code is as old as my college days take me, but as soon as I migrated, everything ran smoothly.

Pretty cool stuff, this ObjC/Swift thingie…