A mutable pointer-to-ObjC-pointer argument.
- Xcode 6.0.1+
- Swift Standard Library
This type has implicit conversions to allow passing any of the following to a C or ObjC API:
nil, which gets passed as a null pointer,
an inout argument of the referenced type, which gets passed as a pointer to a writeback temporary with autoreleasing ownership semantics,
Unsafe, which is passed as-is.
Passing pointers to mutable arrays of ObjC class pointers is not directly supported. Unlike
Autoreleasing must reference storage that does not own a reference count to the referenced value. UnsafeMutablePointer’s operations, by contrast, assume that the referenced storage owns values loaded from or stored to it.
This type does not carry an owner pointer unlike the other C*Pointer types because it only needs to reference the results of inout conversions, which already have writeback-scoped lifetime.