Why does my @lazy property crash, but if I make it non lazy it works?

Question

I have a problem with lazy properties. I thought I got them but maybe I didn\'t / maybe it is a bug

I have a lazy array in my class

@lazy var entered         


        

Answer 1

After some trial, I found something quite odd.

First of all, if we wrap the var inside a class, it simply works:

class RegionManager {
    @lazy var enteredRegions = Array()
}

In AppDelegate, I declared a @lazy var regManager = RegionManager().

Then, in application:didFinishLaunching:, I modify and use the value, it works without spitting a word:

regManager.enteredRegions.append("New!")
println("Regions: \(regManager.enteredRegions)") // Regions: [New!]

After this, I tried to change to some native values, for example, String, Int and so on, they all fail.

So, my guess is that this strange behaviour is actually a bug of the compiler itself, it may be rooted in some optimization for native types, maybe there's a inner pool or what that apple doesn't tell us.