That’s just a C enum interfaced in Swift. You can’t instantiate it, and it has no methods or any kind of functionality. It’s effective a list of numbers.

What are you expecting the documentation to say here? It will make more sense when you find where it’s used.

Edit: First link on the bottom explains exactly what it’s used for. https://developer.apple.com/documentation/avfoundation/retri...

struct AVMetadataKeySpace - a unique unit representing each of the metadata key spaces supported by AVFoundation.

? Did you read the link? It’s used to query collections of keys grouped by the KeySpace categories, instead of a single item per key. Makes sense to me.

There’s plenty of other poorly documented Apple APIs (io_surface), but this isn’t one of them.

> It’s used to query collections of keys grouped by the KeySpace categories

Sounds like something that should be mentioned in the opening sentence of https://developer.apple.com/documentation/avfoundation/avmet...

The struct is only named on the link you provided, not documented. So thanks for showing the absolute irony of it not being greatly documented, allowing people to misinterpret what it means.

Because it’s a boring enum in C, auto translated to a swift struct.

And if you’re reading the documentation because you do development, then you would already know that the header files are installed on your computer and you can trivially verify that there is nothing to document because it’s just a query key.

Enums get documented everywhere else. If nothing else, you need the range of options!

Going off to read the header file means it isn't documented.