For this code
let documentsPath = NSSearchPathForDirectoriesInDomains(.DocumentDirectory, .UserDomainMask, true)[0] as! NSString
I will have forgot what the third argument stands for, soon.
For some reason Swift (2.0) doesn't allow me to label the arguments like that:
let documentsPath = NSSearchPathForDirectoriesInDomains(directory: .DocumentDirectory,
domainMask: .UserDomainMask, expandTilde: true)[0] as! NSString // error
I really hope I'm missing something!
Or rather: I really hope I don't have to miss the single best feature from Objective-C.
It has to do with the way the function is defined. If it isn't defined with named arguments, you can't call it with named arguments.
NSSearchPathForDirectoriesInDomains is either a C style function (not a method) or a compiler macro that generates inline code. (It looks to me like it's a C function.) Neither of those accept named arguments, so you can't.
If you really want to stay away from unnamed arguments, create a utilities class that provides glue code that accepts named arguments and then calls the function in question. That way you encapsulate the old-style code in only one place. There will be a (tiny) performance cost to the extra function call, but in nearly all cases it will be unnoticeable.