I'm having trouble understanding why the following code is trying to unwrap an Optional.
////////
class Proxy<T> {
var value:T
init(_ value:T) {
self.value = value
}
}
func setter<T>(p:Proxy<T>) -> Any? -> () {
return {p.value = $0 as! T}
}
var i = Proxy<Int?>(0), s = setter(i)
s(2)
i.value // => 2
s(nil) // => fatal error: unexpectedly found nil while unwrapping an Optional value
////////
My understanding is that since T is `Int?` here, the setter should be doing (nil as! Int?), which doesn't cause an error. What am I missing?
I'm having trouble understanding why the following code is trying to unwrap an Optional.
////////
class Proxy<T> {
var value:T
init(_ value:T) {
self.value = value
}
}
func setter<T>(p:Proxy<T>) -> Any? -> () {
return {p.value = $0 as! T}
}
var i = Proxy<Int?>(0), s = setter(i)
s(2)
i.value // => 2
s(nil) // => fatal error: unexpectedly found nil while unwrapping an Optional value
////////
My understanding is that since T is `Int?` here, the setter should be doing (nil as! Int?), which doesn't cause an error. What am I missing?
You're right, it should be able to successfully cast a `nil` Any? to a nil `Int?. This is a bug. If you have time, could you write up a report on bugs.swift.org?
-Joe
···
On May 15, 2016, at 4:13 PM, Michael Gardner via swift-users <swift-users@swift.org> wrote:
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