Swift: Beta 5
The more things change
In the fast-moving world of Swift, I'm a day late and that might as well be a year. But I'm also a developer so I just can't help myself. Let's dive into the changes in Beta 5!
Optionals
- As expected, the null coalescing operator was added
??
and lazily evaluates the right-hand side again as you'd . . .
Swift: Wherein I do a horrible thing
Don't do this; code responsibly
Please don't do this. It's horrible, unsupported, and may crash your program.
That said, let's demangle a class name by calling an internal Swift library function.
@asmname("swift_demangleSimpleClass")
func demangleSimpleClass(mangledName: ConstUnsafePointer<Int8>,
moduleName: UnsafePointer . . .
Swift: Testing Privates
There's an awful joke in here somewhere
David Owens II writes about Swift access control and unit tests. He's currently adding his source files directly to the unit test target so the internal members are visible to the tests.
That's probably the best solution possible currently, but I'm filing a radar to add the equivalent of InternalsVisibleTo
. In C#, that . . .
Swift: Should We Make Optionals Clearer?
Who wants to live without extensions
Optionals are great, but there are some improvements that might make code clearer and more explicit. I also want to acknowledge that in some cases you don't actually care if the value is nil or not, you just want to provide an alternate value if it is; that's usually called the null coalescing operator, but Swift doesn't currently . . .
Swift: Pointer Arithmetic
Abandon all hope of safety
Update: I originally did not make it clear but if Swift knows the type of the unsafe pointer then arithmetic will operate on sizeof(T)
not on bytes! The same goes for alloc
. So my example below with an UnsafePointer<Float32>
will jump forward 25 * sizeof(Float32)
bytes.
I've seen a lot of people wondering how to do raw . . .
Swift: Notable Beta 4 Changes
Prayers answered, denied
Here are some of the more notable Swift changes as of Beta 4:
Access Control
The new access control keywords are available:
modifier | |
---|---|
private | can only be accessed from the source file where defined |
internal | can only be accessed from the current target where . . . |
Swift: Let's Query DNS
Interop in the real world
So far we've been going over some of the interop capabilities in Swift, but today I want to switch gears a bit and actually put this stuff to use. Along the way we'll discover some annoyances and take opportunities not available in Objective-C to remedy them.
Let's say we want to determine if a host is reachable. To do . . .