Xcode 7 contains an Objective-C variant, where you can define a type-hint for (homogenous) NSArray
return values and properties, defined such as NSArray&l
The lightweight generics introduced in Xcode 7 are just compile time hints to help the compiler raise warnings, but at run time you get the same old behavior with your variable being just NSArray
s of id
s.
Source: WWDC '15 "Swift and Objective-C Interoperability" session
See the transcript of the talk:
So the entire lightweight generics feature is based on a type erasure model. Which means that the compiler has all of this rich static type information but it erases that information when generating code.